Objective:To construct a machine learning classification prediction model using planning-omics (planomics) features to predict the γ pass rate of intensity-modulated radiotherapy (IMRT) plan dose verification in fixed-field thoracic tumors, and evaluate the application of planomics in radiotherapy quality assurance.Methods:The fixed-field IMRT plans of 240 patients with chest tumors admitted to Department of Radiotherapy, Henan Cancer Hospital from August 2022 to March 2023 were retrospectively analyzed. All plans underwent dose verification using the electronic portal imaging system detector on the Varian accelerator to collect field dose data. The dose verification results were analyzed through Portal Dosimetry in the treatment planning system of Eclipse. The γ pass rate standard was set at 2%/2 mm with a 10% dose threshold. From the planning documents, 48 conventional planning features, 2476 planomics features, and the combination of the previous two feature sets were extracted. Subsequently, an auto-encoder classification model was constructed. To evaluate the classification efficacy of various feature sets, 20 random train-test divisions were conducted by calculating the area under the receiver operating characteristic curve (AUC) values along with the accuracy rates.Results:After the feature selection, 2 conventional features and 16 planomics features were finally selected. In the testing set, the AUC values for the model using combined features, planomics features, and conventional planned features were 0.802±0.030, 0.740±0.069, and 0.673±0.083, respectively. In contrast, in the training set, these AUC values were 0.844±0.074, 0.816±0.047, and 0.687±0.036, respectively. The accuracy rates were 0.752±0.083, 0.703±0.110, and 0.648±0.081 in the testing set, and 0.753±0.098, 0.751±0.075, and 0.624±0.054 in the training set for the combined, planomics, and conventional planning feature sets, respectively.Conclusions:For thoracic fixed-field adjusted radiotherapy planning, the machine learning method based on planomics features can be utilized to build a classification model for predicting the γ pass rate. Combining planomics features with conventional planned features can enhance the predictive performance of the classification models.

Objective:To evaluate the detection capability of the contrast-enhanced three-dimensional turbo spin-echo (CE-SPACE) sequence for brain metastases (BM), aiming to provide evidence for precise target delineation in stereotactic radiotherapy (SRT).Methods:A total of 123 BM patients who received radiotherapy at the Affiliated Cancer Hospital of Zhengzhou University from May to November 2024 were enrolled. All patients underwent contrast-enhanced (CE) MRI and CT scans in the same treatment position, with images rigidly registered in the Eclipse planning system. Two experienced radiation oncologists independently delineated BM lesions on CE-MPRAGE and CE-SPACE sequences in a blinded manner. Patients were divided into the delayed group (10 min, n=61) and a priority group (5 min, n=62) based on the time interval between gadolinium injection and CE-SPACE acquisition. The non-parametric Wilcoxon rank-sum test was used to compare the lesion counts and volume differences between the two imaging sequences. Point-biserial correlation analysis was performed to assess the correlation between the additional lesions identified by CE-SPACE and lesion volume. Results:The overall analysis demonstrated that CE-SPACE detected 421 BM lesions, achieving an 8.2% higher detection rate than CE-MPRAGE ( Z=3.78, P<0.001). In terms of lesion volume, the median BM lesions volume identified by CE-SPACE [0.30(0.07,1.53)cm 3] was 8.7% larger than that by CE-MPRAGE [0.23 (0.04, 1.34) cm 3] ( Z=12.88, P<0.001). CE-SPACE demonstrated superior sensitivity for lesions ≤ 0.06 cm3, with negative correlation between the number of additional lesions detected and lesion volume ( r=-0.104, P=0.034). Subgroup analysis revealed that in the delayed group, CE-SPACE detected significantly more lesions [median 2 (1, 3.5) vs. 2 (1, 3), P=0.002] and larger volumes [0.39 (0.08, 2.24) cm3 vs. 0.29 (0.05, 1.99) cm3, P<0.001] than CE-MPRAGE. In the priority group, CE-SPACE detected significantly larger lesion volumes [0.55 (0.09, 2.06) cm3 vs. 0.45 (0.08, 1.88) cm3, P<0.001], but no significant difference was observed in lesion counts between two sequences ( P=0.059). Conclusions:Three-dimensional CE-SPACE sequence offers superior detection sensitivity for small BM (≤ 0.06 cm3), providing crucial guidance for accurate target delineation in SRT.

Objective:To construct a machine learning classification prediction model using planning-omics (planomics) features to predict the γ pass rate of intensity-modulated radiotherapy (IMRT) plan dose verification in fixed-field thoracic tumors, and evaluate the application of planomics in radiotherapy quality assurance.Methods:The fixed-field IMRT plans of 240 patients with chest tumors admitted to Department of Radiotherapy, Henan Cancer Hospital from August 2022 to March 2023 were retrospectively analyzed. All plans underwent dose verification using the electronic portal imaging system detector on the Varian accelerator to collect field dose data. The dose verification results were analyzed through Portal Dosimetry in the treatment planning system of Eclipse. The γ pass rate standard was set at 2%/2 mm with a 10% dose threshold. From the planning documents, 48 conventional planning features, 2476 planomics features, and the combination of the previous two feature sets were extracted. Subsequently, an auto-encoder classification model was constructed. To evaluate the classification efficacy of various feature sets, 20 random train-test divisions were conducted by calculating the area under the receiver operating characteristic curve (AUC) values along with the accuracy rates.Results:After the feature selection, 2 conventional features and 16 planomics features were finally selected. In the testing set, the AUC values for the model using combined features, planomics features, and conventional planned features were 0.802±0.030, 0.740±0.069, and 0.673±0.083, respectively. In contrast, in the training set, these AUC values were 0.844±0.074, 0.816±0.047, and 0.687±0.036, respectively. The accuracy rates were 0.752±0.083, 0.703±0.110, and 0.648±0.081 in the testing set, and 0.753±0.098, 0.751±0.075, and 0.624±0.054 in the training set for the combined, planomics, and conventional planning feature sets, respectively.Conclusions:For thoracic fixed-field adjusted radiotherapy planning, the machine learning method based on planomics features can be utilized to build a classification model for predicting the γ pass rate. Combining planomics features with conventional planned features can enhance the predictive performance of the classification models.

Objective:To evaluate the detection capability of the contrast-enhanced three-dimensional turbo spin-echo (CE-SPACE) sequence for brain metastases (BM), aiming to provide evidence for precise target delineation in stereotactic radiotherapy (SRT).Methods:A total of 123 BM patients who received radiotherapy at the Affiliated Cancer Hospital of Zhengzhou University from May to November 2024 were enrolled. All patients underwent contrast-enhanced (CE) MRI and CT scans in the same treatment position, with images rigidly registered in the Eclipse planning system. Two experienced radiation oncologists independently delineated BM lesions on CE-MPRAGE and CE-SPACE sequences in a blinded manner. Patients were divided into the delayed group (10 min, n=61) and a priority group (5 min, n=62) based on the time interval between gadolinium injection and CE-SPACE acquisition. The non-parametric Wilcoxon rank-sum test was used to compare the lesion counts and volume differences between the two imaging sequences. Point-biserial correlation analysis was performed to assess the correlation between the additional lesions identified by CE-SPACE and lesion volume. Results:The overall analysis demonstrated that CE-SPACE detected 421 BM lesions, achieving an 8.2% higher detection rate than CE-MPRAGE ( Z=3.78, P<0.001). In terms of lesion volume, the median BM lesions volume identified by CE-SPACE [0.30(0.07,1.53)cm 3] was 8.7% larger than that by CE-MPRAGE [0.23 (0.04, 1.34) cm 3] ( Z=12.88, P<0.001). CE-SPACE demonstrated superior sensitivity for lesions ≤ 0.06 cm3, with negative correlation between the number of additional lesions detected and lesion volume ( r=-0.104, P=0.034). Subgroup analysis revealed that in the delayed group, CE-SPACE detected significantly more lesions [median 2 (1, 3.5) vs. 2 (1, 3), P=0.002] and larger volumes [0.39 (0.08, 2.24) cm3 vs. 0.29 (0.05, 1.99) cm3, P<0.001] than CE-MPRAGE. In the priority group, CE-SPACE detected significantly larger lesion volumes [0.55 (0.09, 2.06) cm3 vs. 0.45 (0.08, 1.88) cm3, P<0.001], but no significant difference was observed in lesion counts between two sequences ( P=0.059). Conclusions:Three-dimensional CE-SPACE sequence offers superior detection sensitivity for small BM (≤ 0.06 cm3), providing crucial guidance for accurate target delineation in SRT.

Objective:To investigate the application value of virtual reality laparoscopic simulator training in laparoscopic transabdominal preperitoneal hernioplasty (TAPP).Methods:The prospective cohort study was conducted. Twenty young physicians from The First Affiliated Hospital of Harbin Medical University with ≥3 years of clinical experience in general surgery and no foundation in laparoscopy were selected for training during July to August 2023. Physicians were divided into two groups based on random number table method. Physicians undergoing virtual reality laparoscopic simulator training were divided into the virtual reality group, and physicians undergoing regular laparoscopic simulator training were divided into the regular group. Two groups of physicians were trained using laparoscopic simulator for 10 days (2 hours for each skill, with a total of 6 hours per day for 3 skills), and the training covered basic laparoscopic surgical skills such as clamping, cutting and suturing and knotting. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups were conducted using the independent sample t test and the paired ttest was used for intra group comparison. Measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers, and comparison between groups were conducted using the chi-square test. Results:(1) Physicians situation before training. A total of 20 physicians were selected for eligibility. There were 13 males and 7 females, aged 31(range, 30?34)years. There are 7 males and 3 females in the virtual reality group, with age of (31.5±1.4)years and the TAPP simulation surgery time of (42±4)minutes before training. There are 6 male and 4 female students in the regular group, with age of (31.2±1.0)years and the TAPP simulation surgery time of (42±4)minutes before training. There was no significant difference in gender, age, TAPP simulation surgery time between the two groups of physicians ( P>0.05), confounding bias ensured comparability. (2) Basic skills of physicians before and after training. For physicians in the virtual reality group, the clamping score was 5.1±1.0, the cutting score was 4.9±1.0, the suturing and knotting score was 4.7±1.5 before training. The clamping score was 8.0±1.3, the cutting score was 7.9±1.5, the suturing and knotting score was 6.6±1.3 after training. There were significant differences in the above indicators before and after training ( t=?5.75, ?5.21, ?3.07, P<0.05). For physicians in the regular group, the clamping score was 5.3±1.0, the cutting score was 5.0±1.2, the suturing and knotting score was 4.3±1.5 before training. The clamping score was 7.1±1.2, the cutting score was 6.7±1.3, the suturing and knotting score was 5.7±1.1 after training. There were significant differences in the above indicators before and after training ( t=?3.73, ?3.16, ?2.42, P<0.05). (3) Completion of simulated surgical situations before and after training. The time of completing TAPP simulation surgery for virtual reality group after training was (29±3)minutes, versus (42±4)minutes before training, showing a significant difference before and after training ( t=7.69, P<0.05). The time of completing TAPP simulation surgery for regular group after training was (36±4)minutes, versus (42±4)minutes before training, showing a significant difference before and after training ( t=3.75, P<0.05). The time of completing TAPP simulation surgery of virtual reality group after training was shorter than that of regular group, showing a significant difference between the two groups ( t=?3.89, P<0.05). Conclusion:Both of virtual reality and regular laparoscopic simulator can enhance the basic laparoscopic surgical skills and the proficiency of TAPP simulation surgery of physicians, and the training effect of virtual reality laparoscopic simulators is better.

OBJECTIVE: To design and construct a graphene oxide (GO)/silver nitrate (Ag₃PO₄)/chitosan (CS) composite coating for rapidly killing bacteria and preventing postoperative infection in implant surgery. METHODS: GO/Ag₃PO₄ composites were prepared by ion exchange method, and CS and GO/Ag₃PO₄ composites were deposited on medical titanium (Ti) sheets successively. The morphology, physical image, photothermal and photocatalytic ability, antibacterial ability, and adhesion to the matrix of the materials were characterized. RESULTS: The GO/Ag₃PO₄ composites were successfully prepared by ion exchange method and the heterogeneous structure of GO/Ag₃PO₄ was proved by morphology phase test. The heterogeneous structure formed by Ag₃PO₄ and GO reduced the band gap from 1.79 eV to 1.39 eV which could be excited by 808 nm near-infrared light. The photothermal and photocatalytic experiments proved that the GO/Ag₃PO₄/CS coating had excellent photothermal and photodynamic properties. In vitro antibacterial experiments showed that the antibacterial rate of the GO/Ag₃PO₄/CS composite coating against Staphylococcus aureus reached 99.81% after 20 minutes irradiation with 808 nm near-infrared light. At the same time, the composite coating had excellent light stability, which could provide stable and sustained antibacterial effect. CONCLUSION GO/Ag₃PO₄/CS coating can be excited by 808 nm near infrared light to produce reactive oxygen species, which has excellent antibacterial activity under light.
Chitosan ; Silver Nitrate ; Titanium ; Anti-Bacterial Agents/pharmacology* ; Coloring Agents

Gallbladder carcinoma is a common malignant tumor of the biliary system characterized by poor specificity of early symptoms， a high degree of malignancy， and rapid progression， and it is difficult to make an early diagnosis. Gallstones and gallbladder polyps are considered the most common risk factors for gallbladder carcinoma. Ultrasound is the preferred examination， while CT， MRI， and PET also have their own advantages. There is a lack of radical treatment methods for gallbladder carcinoma， and surgical operation remains the preferred treatment method for gallbladder carcinoma； however， due to the rapid progression of this disease， most patients have lost the opportunity for surgery at the time of diagnosis. A combination of various treatment modalities， such as radiochemotherapy， targeted therapy， and immunotherapy， has improved the prognosis of patients to a certain extent， but with an unsatisfactory long-term therapeutic effect. Therefore， it is of particular importance to give priority to prevention rather than treatment and emphasize early identification and treatment.

Objective:To investigate the anatomical characteristics of human hepatic anterior fissure vein.Methods:The retrospective and descriptive study was used. A total of 22 adult cadaver specimens were collected from the Department of Human Anatomy of Harbin Medical University from March 2018 to March 2021. There were 15 males and 7 females, aged 45(range, 18?75)years. Observation indicators: (1) recognition rate of hepatic anterior fissure vein and the location of hepatic anterior fissure vein merging into hepatic vein; (2) length of hepatic anterior fissure vein and the opening diameter of hepatic anterior fissure vein merging into hepatic vein; (3) location of hepatic anterior fissure vein and the ventral hepatic vein of segment Ⅷ of liver (V8v) as well as V8v condition; (4) relationship among hepatic anterior fissure vein, anterior ventral portal vein and anterior dorsal portal vein. Measurement data with normal distribution were represented as Mean± SD, and t test was used for comparison between groups. Measurement data with skewed distribution were represented as M(range), and count data were expressed as absolute numbers or percentages. Results:(1) Recognition rate of hepatic anterior fissure vein and the location of hepatic anterior fissure vein merging into hepatic vein. The recognition rate of hepatic anterior fissure vein of 22 liver samples was 90.9% (20/22). There were 9.1%(2/22) of liver samples without hepatic anterior fissure vein. The proportions of hepatic anterior fissure vein merging into proximal middle hepatic vein and proximal right hepatic vein were 19/20 and 1/20, respectively. There was no liver sample with hepatic anterior fissure vein merging into distal middle hepatic vein and distal right hepatic vein. (2) Length of hepatic anterior fissure vein and the opening diameter of hepatic anterior fissure vein merging into hepatic vein. In the 20 liver samples with hepatic anterior fissure vein, the length of hepatic anterior fissure vein was (6.41±1.26)cm, and the opening diameter of hepatic anterior fissure vein merging into hepatic vein was (0.38±0.10)cm. (3) Location of anterior fissure vein and the V8v and V8v condition. In the 22 liver samples, there were 25 V8v branches merging into the proximal middle hepatic vein, with the V8v length as (3.83±0.36)cm and the V8v diameter as (0.16±0.08)cm. In the 17 liver samples with both hepatic anterior fissure vein and V8v, the proportion of V8v merging into hepatic anterior fissure vein and then into middle hepatic vein was 14/17, the proportion of hepatic anterior fissure vein and V8v merging into middle hepatic vein separately was 3/17, and there was no liver sample with hepatic anterior fissure vein merging into right hepatic vein and V8v merging into middle hepatic vein. (4) Relationship among hepatic anterior fissure vein, anterior ventral portal vein and anterior dorsal portal vein. Of the 20 liver samples with hepatic anterior fissure vein, the hepatic anterior fissure vein of 16 liver samples could be used as the demarcation mark of anterior ventral segment and anterior dorsal segment of hepatic right anterior region. The distance between the hepatic anterior fissure vein and anterior ventral portal vein was (1.40±0.43)cm, and that between the hepatic anterior fissure vein and anterior dorsal portal vein was (1.46±0.63)cm, showing no significant difference between them ( t=1.00, P>0.05). Conclusion:The hepatic anterior fissure vein exists in most normal adult livers, and it mostly merges into proximal middle hepatic vein. The hepatic anterior fissure vein can be identified by the condition of V8v. The hepatic anterior fissure vein can be used as the demarcation mark of anterior ventral segment and anterior dorsal segment of hepatic right anterior region.

Objective:To develop a verification platform based on Monte Carlo (MC) for independent dose verification of volumetric modulated arc therapy (VMAT) plans.Methods:The head model including collimator of Varian TrueBeam linear accelerator was constructed by using EGSnrc/BEAMnrc, and the independent dose verification platform for the patients’ VMAT plans was built based on the head model and an in-house code. The percent depth dose (PDD) curves and off-axis ratios for different field sizes, the dose distribution of two irregular fields and three VMAT plans of the head and neck, chest, and pelvis were simulated using the platform. The simulated results of the PDD curves and the off-axis ratios of different field sizes were compared with the blue water measurement results. The difference between the irregular fields and the actual ArcCHECK measurements was also investigated. Besides, the differences among the MC simulated dose, TPS calculated dose and the ArcCHECK measured dose were analyzed by several methods, such as γ analysis and dose-volume histogram to verify whether the platform could be independently employed for dose verification.Results:The MC simulated results of PDD curves and off-axis ratios from 4 cm×4 cm to 40 cm×40 cm were in good agreement with the measured results. And the γ passing rates between the MC simulation and the ArcCHECK measurement for the irregular fields were above 98.1% and 99.1% for 3%/2 mm and 3%/3 mm, respectively. For VMAT plans of three patients, the γ results between the MC simulated dose and ArcCHECK measured dose were better than 93.8% and 95.9% under the criteria of 3%/2 mm and 3%/3 mm respectively. At the same time, the γ passing rates of nasopharyngeal, lung, and rectal cancers were 95.2%, 98.6% and 98.9% based on 3D γ analysis using TPS calculated dose and MC simulated dose under the criteria of 3%/3 mm; the passing rates of these three were 90.3%, 95.1% and 96.7% for 3%/2 mm, respectively.Conclusions:The simulation results of the MC-based verification platform developed in this study show a good agreement with the actual measurement results, and the simulation results are closer to the real dose distribution using the patients’ data. The preliminary results demonstrate that the platform can be used for accurate independent dose verification of VMAT plans.

Objective:To explore the establishment and assessment of the depression model of adult SD rats induced by early maternal infant separation stress combined with adult chronic unpredictable mild stress(CUMS), and to observe the behavior and synaptic protein expression of SD rats.Methods:Twenty-four male rats were randomly divided into three groups: control group (CON group), chronic unpredictable stress group (CUMS group), maternal infant separation combined with chronic unpredictable stress group (MS + CUMS group). The depression model of rats in cums group was established by CUMS, and the depression model of rats in MS + CUMS group was established by maternal infant separation + CUMS. The depression model was evaluated by body mass and appearance observation, sugar water preference experiment, open field test and forced swimming test.Synapse-associated proteins (PSD-95 and synaptophysin (Syn)) of the hippocampus were assayed using Western blot. Syn protein expression was measured by immunohistochemistry.Results:After modeling, compared with CON group, the rats in CUMS group and MS + CUMS group had significantly lower body mass((126.43±3.88) g, (91.04±3.85) g, (69.89±6.67) g; t=5.03, 8.03, both P<0.01), significantly lower sugar water preference((94.21±0.56)%, (79.30±1.13)%, (72.73±1.82)%; t=8.24, 11.87, both P<0.01) and significantly increased immobility time((3.50±0.84)s, (13.59±2.40)s, (15.70±2.97)s; t=3.16, 3.82, both P<0.01). Among them, the body mass and sugar water preference of MS + CUMS group were lower than those of CUMS group ( t=3.00, 3.63; both P<0.01). (2)The center time of the rats in MS+ CUMS group markedly reduced compared with that of CON group((21.41±4.65) s, (8.96±2.37) s; t=2.66, P<0.05). (3)In the immunohistochemistry experiment, compared with the CON group, the percentage of Syn positive area in hippocampus of rats in CUMS group and MS+ CUMS group decreased significantly ((24.42±0.76)%, (14.00±0.95)%, (10.38±1.38)%; t=6.93, 9.33, P<0.01). (4)The results of Western blot showed that compared with CON group, both the expression of PSD-95 ((1.18±0.02), (0.74±0.06), (0.52±0.05), t=6.29, 9.31; both P<0.05) and Syn ((1.12±0.08), (0.95±0.06), (0.90±0.07); t=3.10, 4.04; both P<0.05) in hippocampus of rats in CUMS group and MS+ CUMS group were significantly decreased.And compared with the CUMS group, the expression of PSD-95 in MS+ CUMS group was lower( t=0.93, P<0.05). Conclusion:The method of MS combined with CUMS can effectively induce depression like behavior and decrease the expression of synaptic plasticity related protein of hippocampus in rats.