Objective:To investigate the differences in dosimetric impacts of the systematic errors induced by the leaf positions of a multi-leaf collimator (MLC) on the volumetric modulated arc therapy (VMAT) for patients with different T stages of nasopharyngeal carcinoma (NPC).Methods:A total of 44 patients with T 1-4N 1M 0 NPC were selected to design the VMAT plans using the Pinnacle planning system as the initial plans. The prescribed doses to the primary gross tumor volume (PGTV) were 68-70 Gy in 33 fractions for patients with T 1 and T 2 stage NPC and 71 Gy in 33 fractions for patients with T 3 and T 4 stage NPC. The prescribed doses to other target volumes were identical. In the initial plan files, a systematic error ranging from ±0.2 to ±1 mm was introduced to the position of each MLC leaf, leading to an increase or decrease in the subfield area. Then, potential error plans at the positions of MLC leaves during VMAT treatment were simulated. Dose evaluation indices involved target volumes and organs at risk (OARs). The indices related to target volumes consisted of the D98% of PGTV and PGTVnd, while those concerning OARs included the D0.1 cm 3 of the brainstem, spinal cord, and optic chiasm. Results:After the systematic errors induced by the positions of MLC leaves were introduced, the sensitivity range of each dose index range was (3.87%-9.87%)/mm ( R2 = 0.932-0.998, P < 0.01). Specifically, patients with stage T 4 NPC displayed higher sensitivity to the D98% of PGTV than those with stage T 1, T 2 and T 3 NPC ( Z = -3.12, -2.86, -2.59, P < 0.05), patients with stage T 3 NPC exhibited lower sensitivity to the D0.1 cm 3 of optic chiasm than those with stage T 1 and T 2 NPC ( Z = -2.92, -2.72, P < 0.05), and patients with stage T 4 NPC manifested lower sensitivity to the D0.1 cm 3 of chiasma than those with stage T 1 and T 2 NPC ( Z = -3.51, -3.25, P < 0.05). The relationship between the sensitivity of MU/Gy and PGTV D98% was y=-3.020+ 0.025 x ( r = 0.80, P < 0.05). Conclusion:The MU/Gy in the plans increased with the T stage of NPC, and the D98% of PGTV was more significantly affected by the systematic errors induced by the positions of MLC leaves. After the systematic errors induced by the positions of MLC leaves were introduced into the VMAT plans, doses to patients with T 4 stage NPC changed more significantly than those to patients with other T stages of NPC. Therefore, stricter quality control of leaf positions is required for patients with T 4 stage NPC, and it is recommended that the systematic errors should be less than 0.42 mm.

Ischemic stroke (IS) is a kind of cerebrovascular disease caused by temporary or permanent decrease in local cerebral blood flow. The research of this disease by revealing its pathophysiological process and exploring new therapeutic targets from the cellular and molecular levels has always been the hot spot. In recent years, the competing endogenous RNA (ceRNA) regulatory network mediated by long non-coding RNA (lncRNA) has been proved to play a key role in the pathology and physiology of IS, which can effectively improve the diagnosis, treatment and prognosis of IS. This article aims to describe the mechanism of micro RNA (miRNA) and lncRNA in IS and the role of lncRNA as miRNA's ceRNA in the cell apoptosis, cell viability, angiogenesis, inflammatory response, oxidative stress, and neuroprotection of IS patients, in order to broaden the vision of the occurrence and development of IS and provide new ideas for its diagnosis and treatment.

OBJECTIVE：To estab lish a me thod for simultaneous determination of morroniside ，loganin，echinacoside and acteoside in Huanshao capsules. METHODS ：HPLC method was adopted. The determination was performed on Zhongpuhong RD-C18 column with mobile phase consisted of acetonitrile- 0.1％ formic acid solution （gradient elution ）at the flow rate of 1.0 mL/min. The detection wavelength was set at 240 nm （morroniside，loganin） and 330 nm （echinacoside，acteoside）. The column temperature was set at 35 ℃，and sample size was 10 μL. RESULTS：The linear range were 5.29-105.80 μg/mL for morroniside， 4.49-89.88 mg/L for loganin ，16.26-325.25 mg/L for echinacoside and 16.31-326.25 mg/L for acteoside ，r values were 0.999 9. RSDs of precision ，stability （24 h），reproducibility and durability tests were all lower than 2.0％ . The recoveries were 94.34％ -96.23％（RSD＝0.81％ ，n＝6），97.04％ -98.89％（RSD＝0.73％ ，n＝6），96.23％ -98.08％（RSD＝0.82％ ，n＝6）， 95.40％-98.47％（RSD＝1.23％，n＝6），respectively. The contents of above 4 components in 11 batches of Huanshao Capsules were 0.190-0.704，0.439-0.857，2.723-4.475 and 0.589-1.035 mg/g，respectively. CONCLUSIONS ：Established method is specific ， precise and can be used for content determination of 4 components in Huanshao capsules.

Objective: To compare the accuracies of quantitative computed tomography (CT) parameters and semiquantitative visualscore in evaluating clinical classification of severity of coronavirus disease (COVID-19). Materials and Methods: We retrospectively enrolled 187 patients with COVID-19 treated at Tongji Hospital of Tongji MedicalCollege from February 15, 2020, to February 29, 2020. Demographic data, imaging characteristics, and clinical data werecollected, and based on the clinical classification of severity, patients were divided into groups 1 (mild) and 2 (severe/critical). A semiquantitative visual score was used to estimate the lesion extent. A three-dimensional slicer was used toprecisely quantify the volume and CT value of the lung and lesions. Correlation coefficients of the quantitative CT parameters,semiquantitative visual score, and clinical classification were calculated using Spearman’s correlation. A receiver operatingcharacteristic curve was used to compare the accuracies of quantitative and semi-quantitative methods. Results: There were 59 patients in group 1 and 128 patients in group 2. The mean age and sex distribution of the two groupswere not significantly different. The lesions were primarily located in the subpleural area. Compared to group 1, group 2 hadlarger values for all volume-dependent parameters (p < 0.001). The percentage of lesions had the strongest correlation withdisease severity with a correlation coefficient of 0.495. In comparison, the correlation coefficient of semiquantitative scorewas 0.349. To classify the severity of COVID-19, area under the curve of the percentage of lesions was the highest (0.807;95% confidence interval, 0.744–0.861: p < 0.001) and that of the quantitative CT parameters was significantly higher thanthat of the semiquantitative visual score (p = 0.001). Conclusion The classification accuracy of quantitative CT parameters was significantly superior to that of semiquantitativevisual score in terms of evaluating the severity of COVID-19.

Objective:To investigate the value of texture analysis based on T 2WI and apparent diffusion coefficient (ADC) maps in discriminating low grade from high grade prostate cancer (PCa). Methods:Retrospective analysis was performed on patients who were confirmed to be PCa by pathology after surgery and underwent MRI examination in the department of radiology,Tongji Hospital,Tongji Medical College, Huazhong University of Science and Technology before radical surgery, including routine T 1WI, T 2WI and diffusion weighted imaging (DWI) sequences. 3D data analysis module of the MaZda software was used to manually draw region of interest (ROIs) slice by slice on T 2WI and ADC images, and generate volume of interest (VOI) of the entire tumor. MaZda software was also used to extract texture features. The independent sample t test or Mann-Whitney U test were used to identify the texture features with statistically significant differences between low and high grade PCa groups. Lasso regression model was used to select the best combination of texture features for identifying low and high grade PCa, and then the model was built. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of the model in both training cohort and test cohort. Results:The best texture feature combination selected by Lasso regression model were the S (1, 0, 0) correlation of T 2WI and the S (1, 0, 0) correlation, S (1, -1, 0) sum entropy and vertical-run length nonuniformity of ADC maps. The area under the ROC curve (AUC) of the model in training cohort was 0.823, and the sensitivity and specificity were 70.4% and 80.8%, respectively, which were better than the single texture feature. The AUC of the model in test cohort was 0.714, which was worse than training cohort. Conclusion:The texture analysis of T 2WI and ADC maps is valuable for the identification of low and high grade PCa.

Objective To investigate the value of texture analysis based on MR ADC map of prostate in differentiating between low?grade and high?grade prostate cancer (PCa). Methods PCa confirmed by pathology after radical prostatectomy were analyzed retrospectively, all patients underwent multiparametric MRI before radical prostatectomy, including T1WI,T2WI and DWI. On the ADC map, ROI was drawn manually to encompass the whole tumor by ITK?SNAP software. The python?based pyradiomics package was used to extract 105 texture features. The intraclass correlation coefficient was used to evaluate the repeatability of the texture features. The independent sample t test or Mann?Whitney U test was used to exclude features that had no significant difference between low grade and high grade PCa. Lasso regression model and 5 fold cross validation method were used to obtain texture feature combination of the highest performance and develop a classification modelfor discriminating low from high grade PCa. ROC curve was used to evaluate the diagnostic efficiency of the model. Result Ninety patients with PCa confirmed by pathology after radical prostatectomywere analyzed retrospectively,including 36 patients with low?level PCa (GS≤3+4) and 54 patients with high?level PCa (GS≥4+3). The area under curve of the model was 0.841, with sensitivity 69.6% and specificity 91.2%, which was significantly higher than single texture feature or traditional mean ADC value. Conclusion Texture analysis based on MRI?ADC map of prostate could be used to discriminate low grade PCa from high grade PCa.

Objective: To investigate the value of texture analysis based on MR ADC map of prostate in differentiating between low-grade and high-grade prostate cancer (PCa). Methods: PCa confirmed by pathology after radical prostatectomy were analyzed retrospectively, all patients underwent multiparametric MRI before radical prostatectomy, including T₁WI,T₂WI and DWI. On the ADC map, ROI was drawn manually to encompass the whole tumor by ITK-SNAP software. The python-based pyradiomics package was used to extract 105 texture features. The intraclass correlation coefficient was used to evaluate the repeatability of the texture features. The independent sample t test or Mann-Whitney U test was used to exclude features that had no significant difference between low grade and high grade PCa. Lasso regression model and 5 fold cross validation method were used to obtain texture feature combination of the highest performance and develop a classification modelfor discriminating low from high grade PCa. ROC curve was used to evaluate the diagnostic efficiency of the model. Result: Ninety patients with PCa confirmed by pathology after radical prostatectomywere analyzed retrospectively,including 36 patients with low-level PCa (GS≤3+4) and 54 patients with high-level PCa (GS≥4+3). The area under curve of the model was 0.841, with sensitivity 69.6% and specificity 91.2%, which was significantly higher than single texture feature or traditional mean ADC value. Conclusion Texture analysis based on MRI-ADC map of prostate could be used to discriminate low grade PCa from high grade PCa.

Objective To explore the clinical effect and safety of bedside hand jejunal nutrition tube placement in the treatment of severe acute pancreatitis. Methods The clinical data of 120 patients with severe acute pancreatitis treated in Dazhou Central Hospital from December 2014 to December 2016 were retrospectively analyzed. The patients in the control group(60 cases) were treated with nasogastric tube enteral nutrition on the basis of routine treatment. The patients in the observation group(60 cases) were treated with bedside bare hands on the basis of routine treatment, placement of jejunal feeding tube for jejunal nutrition treatment. The changes of gastrointestinal function,blood and urine amylase content,ICU stay time and the incidence of complications such as reflux and aspiration pneumonia were observed. Results In the observation group,the success rate was 96. 7％ (52 / 60),and the catheterization time was (23. 5 ± 8. 4)min,without any adverse reactions. The recovery time of bowel sounds and anal defecation time of the observation group were (2. 01 ± 0. 47)d and (2. 69 ± 0. 42)d,respectively,which were significantly shorter than those of the control group[(3. 63 ± 1. 52)d and (3. 96 ± 1. 36)d],and the differences were statistically significant(t = 7. 887, 6. 911,all P < 0. 01). There was no statistically significant difference in serum amylase level between the two groups before treatment(t = 1. 364,P > 0. 05). After treatment,the serum amylase level in the observation group was (163 ± 104)IU/ L,which was lower than that in the control group[(302 ± 136)IU/ L](t = 6. 289,P < 0. 01). The recovery time of urinary amylase and the stay time in ICU in the observation group were (9. 28 ± 1. 25)d,(11. 24 ± 0. 84)d, respectively,which were shorter than those in the control group[(16. 32 ± 3. 26) d,(18. 35 ± 2. 42) d],and the differences were statistically significant(t = 15. 619,21. 499,all P < 0. 01). Conclusion Enteral nutrition by beside manual placement of jejunal feeding tube in the treatment of patients with severe acute pancreatitis is simple and safe. It can effectively promote the recovery of intestinal function and shorten the time for ICU. It is worthy of application in clinical practice.

Objective To access the diagnostic value of Prostate Imaging Reporting and Data System (PIRADS version 2)for prostate cancer (PCa) in prostate specific antigen (PSA) grey zone(4-10 ng/mL).Methods Treatment naive PCa and BPH patients with an increase of PSA 4-10 ng/mL from 2200 patients underwent prostate MRI from 2012 to 2016 were included,multiparameter magnetic resonance imaging (mp-MRI) prior biopsy or prostatectomy and clinical data were obtained,mp-MRI were retrospectively analyzed quantitatively by a radiology expert with 15 years experience in urogenital system imaging diagnosis and a doctor with 5 years experience in radiology diagnosis blind to the pathology results according to PIRADS v2,PIRADS v2 score and lesion zone were recorded respectively,in case of disagreement,dicision was made through discuss.TRUS guided biopsy or prostatectomy pathology serves as gold reference.Diagnostic value of PIRADS v2 for PSA grey zone PCa was calculated by receiver operating characteristic (ROC) curve,logistic regression analysis was used to access the risk factors of PCa.Results 15 PCa and 30 BPH patients were in eluded.There was no significant difference between these two groups in age,tPSA,fPSA,f/tPSA,prostate volume and PSA density.The area under ROC curve of PIRADS v2 in diagnosing PCa was 0.932[95 ％ CI 0.822-0.984],P＜0.01.Using a cutoff PIRADS＞4,the diagnosis sensitivity was 88.89 ％,specificity 87.10 ％,and positive predictive value 80 ％,negative predictive value 93.10％,respectively.Logistic regression analysis showed that PIRADS v2 score was an independent risk factor for predicting PCa,with a hazard ratio 17.847[3.745-85.078],P＜0.01.There was a positive correlation between PIRADS v2score and gleason score,r=0.585,P=0.022.Conclusion PIRADS v2 has a significantly high diagnosis value in diagnosing PSA grey zone PCa and a good correlation with pathology results.

Objective The purpose of this study was to compare the image quality of readout-segmented EPI (RS-EPI) and that of standard single-shot echo-planar imaging (SS-EPI) in patients with scrotal diseases. Methods Initial diagnosis of scrotal diseases were included in the prospective study, all patients underwent scrotum routine MRI and RS-EPI, SS-EPI sequence at 3.0 T. A total of 38 patients were recruited qualitative assessment ,and 29 patients proved by operation and pathology (malignant 21 cases and benign 8 cases) were included quantitative analysis.For qualitative comparison of image quality, two readers independently assessed the two sets of DWI, which consisted of identification of structure and geometric distortion of scrotum (epididymis,testes, lesion) using a 5-point Likert scale. For assessment of image parameters, signal-to-noise ratio (SNR), contrast, contrast-to-noise ratio (CNR),apparent diffusion coefficient value of normal testis and testis distortion ratio of anatomical(T2WI)/DWI fusion image were calculated. Inter-observer agreement was assessed with the Kappa statistics, the differences of scores of
RS-EPI and SS-EPI were compared by using Wilcoxon rank-sum test, and image parameters were compared by using paired sample t test. Results There was good reader agreement in the scores, the Kappa value were 0.77, 0.74, 0.80, 0.87. The difference of identification of structure and geometric distortion on RS-EPI and SS-EPI had statistic significance, the RS-EPI was superior to SS-EPI in image quality (all P<0.05).The SNR, contrast of benign lesion for two sequences had no statistic significance(P values were 0.352, 0.124, respectively), but the difference of CNR had statistic significance(P<0.05). The SNR,contrast and CNR of malignant lesion for two sequences had statistic significance (all P<0.05). The mean size of the testis was (35.61 ± 9.78)mm, the mean distance in fusion image of RS-EPI or SS-EPI with T2WI were (3.80 ± 1.32)mm and (7.54 ± 2.62)mm, and the mean distortion ratios of the two set were (11.1 ± 0.6)% and (22.4 ± 19.2)%, respectively, the difference of two sets had statistic significance(P<0.05). There was no significant difference in the ADC obtained by using either DWI method(t=0.396,P=0.796), the mean ADC values of normal testes for RS-EPI and SS-EPI, respectively, were (1.18 ± 0.06) × 10-3mm2/s, (1.24 ± 0.11) × 10-3mm2/s.Conclusion RS-EPI DWI images is a feasible technique in the scrotum for producing high-resolution DWI with reduced geometric distortion and offers potentially superior image quality compared to SS-EPI at 3.0 T.