Background::Histological healing is closely associated with improved long-term clinical outcomes and lowered relapses in patients with ulcerative colitis (UC). Here, we developed a novel diagnostic criterion for assessing histological healing in UC patients.Methods::We conducted a retrospective cohort study in UC patients, whose treatment was iteratively optimized to achieve mucosal healing at Shanghai Tenth People’s Hospital of Tongji University from January 2017 to May 2022. We identified an inflammatory cell enumeration index (ICEI) for assessing histological healing based on the proportions of eosinophils, CD177 + neutrophils, and CD40L + T cells in the colonic lamina propria under high power field (HPF), and the outcomes (risks of symptomatic relapses) of achieving histological remission vs. persistent histological inflammation using Kaplan-Meier curves. Intrareader reliability and inter-reader reliability were evaluated by each reader. The relationships to the changes in the Nancy index and the Geboes score were also assessed for responsiveness. The ICEI was further validated in a new cohort of UC patients from other nine university hospitals. Results::We developed an ICEI for clinical diagnosis of histological healing, i.e., Y = 1.701X 1 + 0.758X 2 + 1.347X 3 - 7.745 (X 1, X 2, and X 3 represent the proportions of CD177 + neutrophils, eosinophils, and CD40L + T cells, respectively, in the colonic lamina propria under HPF). The receiver operating characteristics curve (ROC) analysis revealed that Y <-0.391 was the cutoff value for the diagnosis of histological healing and that an area under the curve (AUC) was 0.942 (95% confidence interval [CI]: 0.905-0.979) with a sensitivity of 92.5% and a specificity of 83.6% ( P <0.001). The intraclass correlation coefficient (ICC) for the intrareader reliability was 0.855 (95% CI: 0.781-0.909), and ICEI had good inter-reader reliability of 0.832 (95% CI: 0.748-0.894). During an 18-month follow-up, patients with histological healing had a substantially better outcome compared with those with unachieved histological healing ( P <0.001) using ICEI. During a 12-month follow-up from other nine hospitals, patients with histological healing also had a lower risk of relapse than patients with unachieved histological healing. Conclusions::ICEI can be used to predict histological healing and identify patients with a risk of relapse 12 months and 18 months after clinical therapy. Therefore, ICEI provides a promising, simplified approach to monitor histological healing and to predict the prognosis of UC.Registration::Chinese Clinical Trial Registry, No. ChiCTR2300077792.

Objective The distribution of the photon energy spectrum in isocenter plane of the medical linear accelerator and the influence of secondary collimator on the photon energy spectrum are studied.Methods Use the BEAMnrc program to simulate the transmission of the 6 MeV electrons and photons in 5 cm×5 cm,10 cm×10 cm,15 cm×15 cm and 20 cm×20 cm fields in treatment head of the medical linear accelerator,where a phase space file was set up at the isocenter plane to record the particle information passing through this plane.The BEAMdp program is used to analyze the phase space file,in order to obtain the distribution of the photon energy spectrum in isocenter plane and the influence of secondary collimator on the photon energy spectrum.Results By analyzing the photon energy spectrum of a medical linear accelerator with a nominal energy of 6 MV,it is found that the secondary collimator has little effect on the photon energy spectrum;different fields have different photon energy spectrum distributions;the photon energy spectrum in different central regions of the same field have the same normalized distribution.Conclusion In the dose calculation of radiation therapy,the influence of photon energy spectrum should be carefully considered.

Objective To investigate the effect of Osteoporosis Self-Assessment Tool for Asia(OSTA)index on brachial ankle pulse wave velocity(baPWV)and its predictive value for peripheral atherosclerosis in menopausal women.Methods A total of 1 138 menopausal women who underwent physical examination at our hospital from January 2022 to December 2022 were enrolled in the study.General clinical data were collected,the OSTA index was calculated,and baPWV was measured.Patients were divided into the control group(n=539)and the peripheral atherosclerosis group(n=599)according to the baPWV values(peripheral atherosclerosis occurs with baPWV≥1 400 cm/s).Linear regression and Logistic regression were used to analyze the effect of OSTA index on baPWV in menopausal women.The predictive value of peripheral atherosclerosis was evaluated using the receiver operating characteristic(ROC)curve.Results The OSTA index was lower in the peripheral atherosclerosis group than that in the control group[-0.40(-2.20,1.00)vs.0.40(-0.60,1.40),P＜0.05].Univariate linear regression analysis was used to conclude that the OSTA index was an influencing factor of baPWV,and after correcting for risk factors,multivariate linear regression analysis indicated that OSTA index still affected the value of baPWV(P＜0.05).The linear regression equation was baPWV=-27.911-39.752×OSTA+6.444×SBP+7.008×DBP+11.506×HCY+27.942×Hs-CRP.Logistic regression analysis suggested that increased OSTA index was a protective factor for peripheral atherosclerosis(OR=0.664,95%CI:0.535-0.823,P＜0.001).ROC curve analysis suggested that OSTA index was-1.25 as the optimal cutoff point,which predicted peripheral atherosclerosis with an area under the curve of 0.619,a sensitivity of 36.2%and a specificity of 86.3%.Conclusion In menopausal women,OSTA index is an influential factor for baPWV,and increased OSTA index is a protective factor against peripheral atherosclerosis,which can be used to predict baPWV value.

Objective:To compare the effects of parameters, such as planning target volume (PTV), calculation grid size, and dose threshold, on the dosimetric verification result of three dosimetric verification systems ArcCHECK, SRS MapCHECK, and 3DMap for stereotactic body radiation therapy (SBRT).Methods:Based on the dosimetric verification result of the SBRT plans of 50 patients, this study compared the effects of PTV (<25 cm 3 and ≥25 cm 3), calculation grid size (1.0, 1.5, and 2.0 mm), and dose threshold (5%, 10%, and 15%) on the γ passing rates of the three dosimetric verification systems at five criteria, i. e., 3 mm/3%, 3 mm/2%, 3 mm/1%, 2 mm/3%, and 2 mm/2%. Results:The changes in PTV affected 3DMap more significantly. With an increase in PTV, the γ passing rates of 3DMap at the criteria of 3 mm/3%, 3 mm/2%, 2 mm/3%, and 2 mm/2% increased by 2.2%, 2.2%, 4.4%, and 4.7% ( t=-2.76, -2.17, -4.72, -3.86, P<0.05), respectively. The increase in the calculation grid from 1.0 mm to 1.5 mm had greater effect on MapCHECK, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 3 mm/1%, 2 mm/3% and 2 mm/2% decreased by 0.7%, 1.1%, 1.7%, 0.9%, 1.5% ( t=-6.15, -6.23, -5.98, -5.11, -8.34, P<0.05), respectively. The increases in the calculation grid from 1.0 mm to 2.0 mm had greater impact on ArcCHECK, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 3 mm/1%, 2 mm/3%, 2 mm/2% decreased by 1.0%, 1.7%, 2.4%, 1.7%, 2.7% ( t=-4.75, -7.3, -8.63, -7.11, -8.26, P<0.05), respectively. The increase in the dose threshold from 5% to 10% had greater impact on ArcCHECK, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 2 mm/3% and 2 mm/2% decreased by 1.1%, 1.4%, 2.5%, and 3.0% ( t=5.20, 5.68, 8.17, 9.99, P<0.05), respectively. Moreover, the increase in the dose threshold from 5% to 15% had more impact on 3DMap, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 2 mm/3%, and 2 mm/2% decreased by 1.6%, 1.7%, 2.8%, and 3.2% ( t=3.25, 2.98, 4.40, 4.21, P<0.05), respectively. Conclusions:Target volume, calculation grid, and dose threshold are influencing factors in the dosimetric verification of three dosimetric verification systems for SBRT. Therefore, the effects of these parameters should be considered for different verification systems in clinical applications.

Objective:To explore the accuracy of array comparative genomic hybridization(aCGH) in the unexpected detection of Duchenne muscular dystrophy ( DMD) gene duplication/deletion in prenatal diagnosis. Methods:A retrospective analysis was performed on 31 cases with DMD gene duplication/deletion detected by aCGH among 5 025 prenatal diagnosis samples without family history of DMD in Henan Provincial People's Hospital from July 2018 to December 2019. The multiplex ligation-dependent probe amplification (MLPA) method was used to verify the above results. The American College of Medical Genetics and Genomics (ACMG) guideline was referred for pathogenicity analysis of the detected duplicates/deletions. Descriptive analysis was adopted in analysis. Results:The total unexpected DMD gene duplication/deletion rate was 0.62% (31/5 025), among which 25 cases were with microduplication/microdeletion ≤ 200 kb and six were >200 kb; there were 24 cases of deletion, seven cases of duplication; exon or intron duplication/deletion were accounted for 19 and 12 cases, respectively. According to the five classification standards of ACMG guideline, there were 17 cases with pathogenic variants and 14 cases with uncertain pathogenicity/likely benign variants. Of the 19 with exon mutations, 17 cases were DMD intragenic variants, and two cases involved variants in and outside DMD gene, which were verified by MLPA whose results were all positive. Conclusions:The duplication/deletion of exon region of DMD gene detected by aCGH technique is accurate and reliable, which plays an important role in the diagnosis of DMD. For these cases involved both internal and external regions of DMD gene, aCGH can identify the upstream and downstream breaking points of DMD gene, thus providing the basis for ACMG grading.

Objective: To compare the dosimetric differences of volumetric modulated arc therapy (VMAT) plans optimized with 3 different fluence smoothing parameters using Monaco treatment planning system. Methods: A total of 15 patients with middle and upper esophageal carcinoma were planned with Low fluence smoothing (Low), Medium fluence smoothing (Medium) and High fluence smoothing(High) during VMAT optimization. The dosimetric differences in D₉₅, D_mean, conformity index (CI), homogeneity index (HI) of targets, dose volume histogram (DVH) of organs at risk (OARs), and monitor unit (MU) were compared. Results: There were no significant differences in D₉₅, D_mean, CI and HI of targets, as well as in V₄₀ and D_mean of the heart, V₁₀, V₂₀ and D_mean of the lung , and segment number among plans optimized with different fluence smoothing techniques (P>0.05). Plans with high fluence smoothing achieved less V₃₀ of heart, D_max of cord PRV(t=-2.167, -0.999, P<0.05), lower MU (t=-3.148, -6.692, P<0.05), but increased V₅ of both lungs (t=1.306, -2.027, P<0.05) compared with plans with Medium and Low fluence smoothing. Plans with low fluence smoothing irradiated higher dose to the V₃₀ and D_mean to heart (t=0.411, 0.589, 0.013, P<0.05), but less V₅ of the lungs (t=0.423, P<0.05) compared with plans with medium fluence smoothing. Conclusions All VMAT plans with 3 different fluence smoothing can meet the clinical requirements. VMAT plans optimized with high fluence smoothing are recommended in the treatment of patients middle and upper thoracic esophageal carcinoma.

Objective:To explore the influence of virtual simulation experiment project on the experimental teaching effect of infectious diseases.Methods:Ten experimental contents were selected, including 3 703 students majoring in clinical five-year program, eight-year program, anesthesia, psychiatry and other majors of Medicine School of Central South University. The teaching effect and students' satisfaction were evaluated through examination and personal questionnaire survey. The measurement data was expressed by (mean ± standard deviation), the counting data was illustrated by percentage. The rate is compared by Chi-square test, and the difference is statistically significant when P<0.05. Results:All the students took part in the examination of 10 items. Except for item 8, the scores of students in all items had a large variance, with almost same number of high score students and low score students. Learning attitude is closely related to learning effect. Among the students who think it's necessary to learn, 20.5% and 53% have excellent learning effect and good learning effect, respectively. Compared with offline experiment teaching, virtual simulation teaching has both advantages and disadvantages, and needs to further improve the satisfaction of students.Conclusion:Virtual simulation teaching of infectious diseases is unable to completely replace offline teaching, and the combination of virtual and reality is more conducive to improving the quality of medical students.

Objective To investigate the potential dosimetric advantages of half jaw volumetric modulated arc therapy ( H-VMAT) applied to the Oropharyngeal Cancer, comparing with full jaw VMAT (F-VMAT) and intensity modulated radiotherapy ( IMRT ). Methods Planning CT images of 10 oropharyngeal cancer patients were retrospectively chosen and transferred to Eclipse treatment planning system v. 11. 0 (Varian Medical Systems, Pala Alto, USA), based on which H-VMAT, W-VMAT, and IMRT plans were created. Two full arcs (360°) were adopted for VMAT planning, and the 7 beams were equally distributed for IMRT planning. The optimization constraints remained the same for the three kinds of plans. The dosimetric parameters such as D2 , D98 , D50 , HI, and CI were evaluated for PGTV, PCTV1, PCTV2, PGTVln, and PCTVln. In addition, the maximum dose (Dmax) and D1 cc(minimum dose received by 1cc) of the brainstem and spinal cord were analyzed respectively. The mean dose ( Dmean ) to the parotids, oral cave, larynx, and cervical normal tissues were also reviewed. The monitor units ( MU) for all treatment plans were recorded. Results Comparisons of the three planning techniques showed that H-VAMT improved the HI and CI of the targets (except PCTV2) significantly (HI: F =3. 959, 6. 764, 10. 581, 6. 770, 13. 040, P<0. 05;CI:F=6. 594, 4. 138, 0. 842, 4. 031, 5. 388, P<0. 05);reduced Dmax(F=4. 509, 20. 331, P<0. 05) and D1 cc for brainstem and spinal cord (F=27. 432, 26. 314, P<0. 05) significantly;reduced Dmean(F=4. 279, 29. 498, 19. 295, P<0. 05) to the normal tissues of the mouth, throat and neck significantly. The V50 of the mouth and throat were slightly lower in IMRT plans (F=8. 140, P<0. 05). IMRT was slightly better than W-VMAT in sparing oral cavity and larynx, but the dose distribution was the worst. The H-VMAT plans showed the best dose distribution in the cervical normal tissues, especially for the lower and posterior parts, where IMRT plans displayed high dose curves. Conclusions H-VMAT is dosimetrically superior than W-VMAT and IMRT for oropharyngeal cancer, which could be considered for clinical applications.

Objective To compare dosimetric parameters between automated and manualvolumetric modulated arc therapy(VMAT) plans in the treatment of postoperative cervical cancer patients,and to investigatethe feasibility and dosimetric advantage of the automated VMAT planning.Methods Automated and manual VMAT plans were generated with Pinnacle3 treatment planning system (TPS) for twenty-three postoperative cervical cancer patients,including eight patients in stage Ⅱ A and fifteen in stage Ⅱ B,respectively.The differences in D D95,conformity index (CI) and homogeneity index (HI) of target,as well as dose volume histogram (DVH) of organs at risk (OAR),planning time,average optimization time and monitor unit (MU) were compared between automated and manual VMAT plans.Results The average D CI and HI of automated VMAT plans were better than those of manual VMAT plans (t=4.65-14.92,P ＜0.05).There was no significant difference in D95 (P ＞0.05).The automated VMAT plans achieved better average dosimetric parameters on OARs compared with the manual VMAT plans (t =3.30-14.42,P ＜ 0.05).Automated VMAT plans had a significantly shorter planning time (72 min,t =3.85,P ＜ 0.05) and interruption frequency (twice,t =5.41,P ＜ 0.05) than manual VMAT plans.However,automated VMAT plans had a higher average MU than manual VMAT plans with an average MU of 819 ± 53 and 638 ± 41 for automated and manual VMAT plans,respectively.Conclusions It is feasible to generate automated VMAT plans with Pinnacle3 TPS for postoperative cervical cancer patients.The automated VMAT plans increase the plan quality and reduce the optimization time compare with manual VMAT plans.Automated technique also eliminates the influence of human factors on the plan quality.

Objective To evaluate the effect of stainless steel applicator on dose distribution in GZP 60 Co brachytherapy source and to obtain the dosimetric parameters of the 60 Co source with stainless steel applicator. Methods Geant4 was employed to obtain the mean adsorption dose of the 60 Co brachytherapy source in the range of 0-10 cm, and the dosimetric parameters were calculated according to the formula proposed by AAPM reports TG43 and TG43U1. The 60 Co source was located in the center of a sphere water phantom with a radius of 30 cm. Results For channel 1 and 2 of GZP 60 Co source, the results of Λ with stainless steel applicator were 1. 014 cGyh-1 U-1( with a difference of 0. 5％ compared with non-applicator) , the results of Λ with stainless steel applicator for channel 3 were 0. 998 cGyh-1 U-1 ( with a difference of 0. 1％ compared with non-applicator) . The radial dose function in the range of 0. 5-10. 0 cm in a longitudinal direction was calculated and the fitting formula for the function was obtained. The polynomial function for the radial dose function and the anisotropy function with a of 0°-175° and an r of 0. 5-10. 0 cm were obtained. Conclusion The dosimetric parameters of the 60 Co source with stainless steel applicator are obtained, which provide more accurate reference data for clinical application. In clinical practice, the effect of stainless steel applicator on dose distribution should be considered.