OBJECTIVE: To estimate the primary electron beam parameters (PEB), including energy, radial intensity distribution and average angular divergence, of the individual linear accelerator using the Monte Carlo method. METHODS: A model of the treatment head and a standard field were built by BEAMnrc, and the dose distribution was simulated in water phantoms by DOSXYZnrc to obtain the percentage depth dose curve and off-axis ratio. By debugging the parameters mentioned above until the simulation and measurement results could match. RESULTS: The simulation and measurement results could achieve the best match when the parameters mentioned above were 6.25 MeV, 0.95 mm and 0.1° respectively. CONCLUSION The PEB of a linear accelerator could have a significant impact on the output beam characteristics. Monte Carlo estimation is one of the most crucial steps in establishing an individual linear accelerator model.
Monte Carlo Method ; Particle Accelerators ; Electrons ; Radiotherapy Dosage ; Phantoms, Imaging

Objective To explore the mechanism of total saponin from Panax japonicus(TSPJ)in alleviating neuroinflammation in experimental autoimmune encephalomyelitis(EAE)based on the activation of microglia mediated by MAPK signaling pathway.Methods In vivo experiments,mice were divided into normal group,model group and TSPJ low-and high-dosage groups.EAE mouse model was induced by myelin oligodendrocyte glycoprotein polypeptide.Each medication group was gavaged with corresponding drug solution once a day for 28 days.The number of Iba-1-positive cells was assessed using immunofluorescence,the protein expressions of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β and MAPK signaling pathway related factors were detected by Western blot.In vitro experiments,murine microglia BV2 were divided into normal group,model group and TSPJ low-and high-dosage groups.LPS+IFN-γ was used to induce M1 polarization of BV2 cells,medication groups were given TSPJ intervention,the content of nitric oxide(NO)in cell supernatant,the expression of M1 microglia markers and MAPK signaling pathway related factors were detected,and ERK and JNK signaling pathway inhibitors were further used to clarify the molecular mechanism of TSPJ antagonizing neuroinflammation.Results The results of in vivo experiments showed that compared with the normal group,the cell body and number of microglia in cerebral cortex of the model group mice increased significantly(P<0.01),and the protein expressions of TNF-α,IL-6,IL-1β,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 significantly increased(P<0.05,P<0.01);compared with the model group,the number of microglia in cerebral cortex of TSPJ low-and high-dosage groups significantly decreased(P<0.01),the expressions of TNF-α,IL-6,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 protein significantly decreased(P<0.05,P<0.01),and the expression of IL-1β protein in TSPJ high-dosage group significantly decreased(P<0.05).The results of in vitro experiments showed that compared with the normal group,the content of NO in cell supernatant of the model group significantly increased(P<0.01),the protein expressions of CD16,CD86,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 significantly increased(P<0.01);compared with the model group,the content of NO in cell supernatant of TSPJ low-and high-dosage groups significantly decreased(P<0.01),and the protein expressions of CD16,CD86,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 significantly decreased(P<0.05,P<0.01).TSPJ combined with ERK and JNK pathway inhibitors could further inhibit the expressions of TNF-α and IL-6,but there was no significant difference compared with inhibitors alone.Conclusion TSPJ can inhibit the activation of microglia by regulating MAPK signaling pathway,thereby reducing EAE induced central nervous inflammation.

Objective: To analyze changes in Rh system antibodies among antibody-positive patients and evaluate the efficacy of Rh phenotype-matched electronic cross-matching (hereinafter referred to as Rh-ECM). Methods: A retrospective analysis was performed on antibody screening data of 48 254 patients in our hospital from December 2023 to March 2025. The antibody screening results were compared between the pre-application phase (n=46 346, control group) and post-application phase (n=48 254, experimental group) of Rh-ECM technology, focusing on the changes in the proportion of Rh system antibodies, with statistical analysis conducted using SPSS 26.0 software. Meanwhile, the initial and re-examination situations of Rh antibody in the antibody screening of approximately 20 000 person-times each before (June 2019 to June 2020, n=21 048) and after (July 2020 to April 2021, n=20 965) of Rh-ECM were evaluated to explore the influence of Rh-ECM on the detection rate of Rh antibody. Results: After Rh-ECM implementation, 345 positive cases (0.7%) (345/48 254) were detected among 48 254 patients, primarily consisting of mns system antibodies (128 cases, 37.1%) (128/345) and rh system antibodies (95 cases, 27.5%) (95/345). Before Rh-ECM implementation, 199 positive cases (0.4%) (199/46 346) were detected among 46 346 patients, with rh system antibodies accounting for 97 cases (48.7%) (97/199). The difference in the composition ratio of Rh antibodies between the two phases was statistically significant (P<0.001), and the relative risk ratio of Rh antibody detection after Rh-ECM implementation was 56.5% compared to before. Another set of data analysis showed that before Rh-ECM, there were 37 cases with initial positive results and 8 cases with re-examination positive results; after Rh-ECM, these numbers were 44 and 2 respectively There was a statistically significant difference in the re-examination positive rate of Rh antibodies between the two stages (P<0.05). Conclusion: The implementation of Rh-ECM technology significantly reduced the proportion of Rh system antibodies among patients with positive antibody screening results. This suggests that Rh-ECM can effectively reduce the detection rate of Rh antibodies, which may be related to the reduced risk of antibody production due to Rh-matched transfusion, thus improving transfusion safety. Therefore, Rh-ECM is worthy of broader promotion in clinical transfusion testing.

Objective To observe the effectiveness and safety of DiaSphere embolized microsphere TACE for treating primary hepatocellular carcinoma(HCC).Methods Totally 188 patients with HCC were prospectively enrolled and randomly assigned to research group(n=93)and control group(n=95),who underwent TACE with DiaSphere embolized microspheres and Embosphere embolized microspheres,respectively.The incidence of TACE-related adverse events were recorded.The therapeutic efficacy 1 month after the first TACE,also 1 and 3 months after the last TACE,and liver functions 1 month after the first and last TACE were compared between groups.Results In research group,there were 69 cases underwent 1 time TACE,22 cases underwent 2 times and 2 cases underwent 3 times TACE,while in control group,there were 82 cases underwent 1 time and 13 cases underwent 2 times TACE,respectively.No statistical difference of the incidence of adverse events was found between groups(77.42%[72/93]vs.76.84%[73/95],P=1.000).One month after the first TACE,7 cases in research group and 11 cases in control group were lost to follow-up,respectively.One month after the last TACE,12 cases were lost to follow-up in both groups,and 3 months after the last TACE,28 cases were lost to follow-up in both groups.No significant difference of objective response rate nor disease control rate was found between groups at the above time points(all P＞0.05).One month after the first and last TACE,liver function indicators were not different between groups(all P＞0.05).Conclusion Both the short-term efficacy and safety of TACE with DiaSphere embolized microspheres for treating HCC were good.

Objective To observe the effectiveness and safety of DiaSphere embolized microsphere TACE for treating primary hepatocellular carcinoma(HCC).Methods Totally 188 patients with HCC were prospectively enrolled and randomly assigned to research group(n=93)and control group(n=95),who underwent TACE with DiaSphere embolized microspheres and Embosphere embolized microspheres,respectively.The incidence of TACE-related adverse events were recorded.The therapeutic efficacy 1 month after the first TACE,also 1 and 3 months after the last TACE,and liver functions 1 month after the first and last TACE were compared between groups.Results In research group,there were 69 cases underwent 1 time TACE,22 cases underwent 2 times and 2 cases underwent 3 times TACE,while in control group,there were 82 cases underwent 1 time and 13 cases underwent 2 times TACE,respectively.No statistical difference of the incidence of adverse events was found between groups(77.42%[72/93]vs.76.84%[73/95],P=1.000).One month after the first TACE,7 cases in research group and 11 cases in control group were lost to follow-up,respectively.One month after the last TACE,12 cases were lost to follow-up in both groups,and 3 months after the last TACE,28 cases were lost to follow-up in both groups.No significant difference of objective response rate nor disease control rate was found between groups at the above time points(all P＞0.05).One month after the first and last TACE,liver function indicators were not different between groups(all P＞0.05).Conclusion Both the short-term efficacy and safety of TACE with DiaSphere embolized microspheres for treating HCC were good.

Objective To explore the mechanism of total saponin from Panax japonicus(TSPJ)in alleviating neuroinflammation in experimental autoimmune encephalomyelitis(EAE)based on the activation of microglia mediated by MAPK signaling pathway.Methods In vivo experiments,mice were divided into normal group,model group and TSPJ low-and high-dosage groups.EAE mouse model was induced by myelin oligodendrocyte glycoprotein polypeptide.Each medication group was gavaged with corresponding drug solution once a day for 28 days.The number of Iba-1-positive cells was assessed using immunofluorescence,the protein expressions of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β and MAPK signaling pathway related factors were detected by Western blot.In vitro experiments,murine microglia BV2 were divided into normal group,model group and TSPJ low-and high-dosage groups.LPS+IFN-γ was used to induce M1 polarization of BV2 cells,medication groups were given TSPJ intervention,the content of nitric oxide(NO)in cell supernatant,the expression of M1 microglia markers and MAPK signaling pathway related factors were detected,and ERK and JNK signaling pathway inhibitors were further used to clarify the molecular mechanism of TSPJ antagonizing neuroinflammation.Results The results of in vivo experiments showed that compared with the normal group,the cell body and number of microglia in cerebral cortex of the model group mice increased significantly(P<0.01),and the protein expressions of TNF-α,IL-6,IL-1β,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 significantly increased(P<0.05,P<0.01);compared with the model group,the number of microglia in cerebral cortex of TSPJ low-and high-dosage groups significantly decreased(P<0.01),the expressions of TNF-α,IL-6,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 protein significantly decreased(P<0.05,P<0.01),and the expression of IL-1β protein in TSPJ high-dosage group significantly decreased(P<0.05).The results of in vitro experiments showed that compared with the normal group,the content of NO in cell supernatant of the model group significantly increased(P<0.01),the protein expressions of CD16,CD86,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 significantly increased(P<0.01);compared with the model group,the content of NO in cell supernatant of TSPJ low-and high-dosage groups significantly decreased(P<0.01),and the protein expressions of CD16,CD86,p-p38/p38,p-JNK/JNK,p-ERK1/2/ERK1/2 significantly decreased(P<0.05,P<0.01).TSPJ combined with ERK and JNK pathway inhibitors could further inhibit the expressions of TNF-α and IL-6,but there was no significant difference compared with inhibitors alone.Conclusion TSPJ can inhibit the activation of microglia by regulating MAPK signaling pathway,thereby reducing EAE induced central nervous inflammation.

[Objective]To investigate primary and secondary transfer of exfoliated cells from human hands on non-porous substrates such as plastic steering wheel or computer mouse.[Methods]DNA detection sensitivity and detection limit for mixed DNA profiling were examined to understand our laboratory's ability to test for trace DNA.Forensic swabs were used to collect samples from volunteers'one-hour-long unwashed hands,substrates touched by volunteers'immediately or 30 min following shaking hands,and individual A's daily-use substrates touched by individual B and then by individual A again.Simulations were conducted to assess the potential for introduction of another person's exfoliated cells from hands into routine casework samples.[Results]Our laboratory can obtain a full DNA profile from as little as 0.020 ng of DNA and detect minor components in a 1:9 mixed DNA sample.85%of samples from unwashed hands yielded a full DNA profile.Primary transfer of a full DNA profile was found in 77%of substrates touched by volunteers'dominant hand 30 min after hand washing,allowing differentiation between good and poor shedders,with no significant difference in genders and substrate types.75%of substrates touched 30 min after hand washing and then immediately following handshaking yielded the other individual's DNA profile(secondary transfer),with the number of short tandem repeat(STR)loci detected ranging from 0 to 23;the percentage and number decreased substantially when the substrates were touched 30 minutes later.No foreign DNA was detected in routine casework samples with introduced exfoliated cells from hands.When two individuals took turns touching items with their hands,the major contributor to the DNA profile was not always the individual who made the last contact.[Conclusions]Primary and secondary DNA transfer can be detected on non-porous substrates,and based on the deposit of hand exfoliated cells,individuals can be categorized as good or poor shedders,which is an important factor affecting detection of DNA transfer.Besides considering the laboratory's DNA detection sensitivity,if DNA is detected on substrates by hand contact,we need to take into account the potential for secondary transfer at different levels of activity when interpreting the results.

Objective To analyze the effects of deep learning image reconstruction(DLIR)and adaptive statistical iterative recon-struction V(ASIR-V)on the imaging quality of chest CT in patient with pulmonary nodules,and to evaluate the differences based on different image reconstruction techniques in the detection of efficiency of computer-aided diagnosis(CAD)for pulmonary nodules.Methods The image data of pulmonary nodules of eighty patients with chest CT screening were reconstructed with ASIR-V 80％,DLIR-low(DLIR-L),DLIR-medium(DLIR-M)and DLIR-high(DLIR-H)images,respectively.The objective image quality and sub-jective image quality of the four groups were compared and analyzed.Objective image quality includes CT value of region of interest(ROI),noise,signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR)and image average gradient.The diagnostic efficacy of CAD in detecting pulmonary nodules of reconstructed images among four groups were further evaluated.Results There were no signifi-cant difference in CT value of ROI of reconstructed images among the four groups(P＞0.05).The noise,SNR and CNR of DLIR-H images were similar to those of ASIR-V 80％(P＞0.05),but significantly better than those of DLIR-L and DLIR-M(P＜0.05).The average gradient of DLIR-L,DLIR-M and DLIR-H images were significantly higher than those of ASIR-V 80％(P＜0.05).The subjective image quality scores of DLIR-L,DLIR-M and DLIR-H images were significantly higher than those of ASIR-V 80％(P＜0.05),and the subjective image quality score of DLIR-H image was the highest.CAD showed the highest true positive rate in DLIR-H images for detecting pulmonary nodules(P＜0.05),and CAD showed the highest false positives per capita in ASIR-V 80％images for detecting pulmonary nodules(P＜0.05).Conclusion The noise,SNR and CNR of DLIR-H images are similar to those of ASIR-V 80％,with the significantly higher image clarity and subjective image quality scores.DLIR-H has advantages in CAD detection of pulmonary nodules,which is an ideal image reconstruction technology for chest CT pulmonary nodule screening.

Pulmonary sarcomatoid carcinoma(PSC)is a rare and highly malignant tumor,which includes the follow-ing five pathologic types:pleomorphic carcinoma,spindle cell carcinoma,giant cell carcinoma,carcinosarcoma and pulmonary blastoma.The onset of PSC is occult with non-specific clinical symptoms and signs.The clinical manifestations include irritat-ing cough,bloody sputum,dyspnea,chest pain and so on,which are closely related to the growth and invasion site of the tumor.PSC tends to metastasize early,so most patients are already in local advanced stage or advanced stage with a median survival of 9 months at the time of hospital visit.A patient with primary PSC which led to 90%stenosis in central airway was treated by com-bined method of vascular and tracheoscopic intervention in our respiratory center.This treatment prolonged the patient's survival time and got a satisfactory effect at 19-month follow-up after surgery.Herein we report the case for clinical reference.

Background and objective As a new technique developed in recent years,bronchoscopic interven-tion therapy has the advantages of minimal invasion,high safety and repeatability.The aim of this study is to investigate the clinical characteristics of bronchopleural fistula(BPF)induced by surgeries for lung malignancies or benign diseases and the effect of bronchoscopic intervention therapy for BPF,so as to provide support for prevention and treatment of BPF.Methods Data 64 patients with BPF who were treated by bronchoscopic intervention in Respiratory Disease Cen-ter of Dongzhimen Hospital,Beijing University of Chinese Medicine from June 2020 to September 2023 were collected.Patients with fistula diameter ≤5 mm were underwent submucous injection of macrogol,combined with blocking therapy with N-butyl cyanoacrylate,medical bioprotein glue or silicone prosthesis.Patients with fistula diameter＞5 mm were im-planted with different stents and cardiac occluders.Locations and characteristics of fistulas were summarized,meanwhile,data including Karnofsky performance status(KPS),shortbreath scale(SS),body temperature,pleural drainage volume and white blood cell count before and after operation were observed.Results For all 64 patients,96 anatomic lung resections in-cluding pneumonectomy,lobectomy and segmentectomy were executed and 74 fistulas occurred in 65 fistula locations.The proportion of fistula in the right lung(63.5％)was significantly higher than that in the left(36.5％).Besides,the right inferior lobar bronchial fistula was the most common(40.5％).After operation,KPS was significantly increased,while SS,body tem-perature,pleural drainage volume and white blood cell count were significantly decreased compared to the preoperative values(P＜0.05).By telephone follow-up or readmission during 1 month to 38 months after treament,median survival time was 21 months.33 patients(51.6％)showed complete response,7 patients(10.9％)showed complete clinical response,18 patients(28.1％)showed partial response,and 6 patients(9.4％)showed no response.As a whole,the total effective rate of broncho-scopic intervention for BPF was 90.6％.Conclusion BPF induced by pulmonary surgery can lead to severe symptoms and it is usually life-threating.Bronchoscopic intervention therapy is one of the fast and effective therapeutic methods for BPF.