The increasing frequency of radiographic diagnostic imaging and the cumulative dose to the public from radiation has raised widespread concerns. However, accurate measurement of the radiation dose received by the human body is difficult to achieve. Monte Carlo simulation, as a numerical computational method guided by probability statistics theory, has been applied to various dose assessments, imaging optimizations, and radiation protection in radiographic diagnostic imaging. We provide a comprehensive review of the principles of the Monte Carlo method, the modelling process of Monte Carlo simulation and the progress of its application to diagnostic radiological dose estimation.

Objective:To investigate the characteristics of the CD8+T cells infiltration from the 4 sub-types in medulloblastoma(MB),to analyze the relationship between CD8+T cells infiltration and prog-nosis,to study the function of C-X-C motif chemokine ligand 11(CXCL11)and its receptor in CD8+T cells infiltration into tumors and to explore the potential mechanism,and to provide the necessary clinico-pathological basis for exploring the immunotherapy of MB.Methods:In the study,48 clinical MB sam-ples(12 cases in each of 4 subtypes)were selected from the multiple medical center from 2012 to 2019.The transcriptomics analysis for the tumor of 48 clinical samples was conducted on the NanoString Pan-Cancer 10360?Panel(NanoString Technologies).Immunohistochemistry(IHC)staining of formalin-fixed,paraffin-embedded sections from MB was carried out using CD8 primary antibody to analyze diffe-rential quantities of CD8+T cells in the MB four subtypes.Through bioinformatics analysis,the relation-ship between CD8+T cells infiltration and prognosis of the patients and the expression differences of various chemokines in the different subtypes of MB were investigated.The expression of CXCR3 receptor on the surface of CD8+T cells in MB was verified by double immunofluorescence staining,and the under-lying molecular mechanism of CD8+T cells infiltration into the tumor was explored.Results:The charac-teristic index of CD8+T cells in the WNT subtype of MB was relatively high,suggesting that the number of CD8+T cells in the WNT subtype was significantly higher than that in the other three subtypes,which was confirmed by CD8 immunohistochemical staining and Gene Expression Omnibus(GEO)database analysis by using R2 online data analysis platform.And the increase of CD8+T cells infiltration was posi-tively correlated with the patient survival.The expression level of CXCL11 in the WNT subtype MB was significantly higher than that of the other three subtypes.Immunofluorescence staining showed the presence of CXCL11 receptor,CXCR3,on the surface of CD8+T cells,suggesting that the CD8+T cells might be attracted to the MB microenvironment by CXCL11 through CXCR3.Conclusion:The CD8+T cells infiltrate more in the WNT subtype MB than other subtypes.The mechanism may be related to the activation of CXCL11-CXCR3 chemokine system,and the patients with more infiltration of CD8+T cells in tumor have better prognosis.This finding may provide the necessary clinicopathological basis for the regulatory mechanism of CD8+T cells infiltration in MB,and give a new potential therapeutic target for the future immunotherapy of MB.

Objective To investigate the effectiveness and safety of volumetric modulated arc therapy (VMAT) hypofractionated radiotherapy and intensity modulated conformal radiotherapy technique (IMRT) conventional fractionated radiotherapy after breast cancer radical operation.Methods Eighty-five patients with breast cancer modified radical operation admitted and treated in this hospital from March 1,2021 to De-cember 30,2021 were selected as the research subjects and divided into the VMAT group (n=41) and the IM-RT group (n=42) according to the random number table method.The VMAT group adopted the hypofrac-tionated radiotherapy,with the single fractionated dose of 2.9 Gy/frequency and radiotherapeutic total dose of 43.5 Gy/15 frequencies;the IMRT group adopted the IMRT conventional fractionated radiotherapy,with the single fractionated dose of 2.0 Gy/frequency and radiotherapeutic total dose of 50.0 Gy/25 frequencies.The planning target region V95,V110,conformity index,homogeneity index,treatment time,V5,V20,V30,average dose (Dmean) in the affected side lung,humeral head Dmean and heart V30,Dmean were compared between the two groups.Meanwhile,local recurrence,distant metastasis,disease-free survival and acute and chronic radiation injury were compared between the two groups.Results Compared with the IMRT group,V95 in the VMAT was higher,V110 and homogeneity index were lower,the treatment time was shorter,V5 in the affected lung,Dmean and Dmean in the affected humeral head were lower,V30 in the affected lung was higher,heart V30 in the left side breast cancer was lower,heart Dmean in the right side breast cancer was lower,and the differences were statistically significant (P<0.05).All patients survived without local relapse.The distant metastasis rate and disease free survival rate had no statistical difference between the two groups (P>0.05).Follow up lasted for 12 months,the incidence rates of grade Ⅰ-Ⅱ acute radiodermatitis,radiation esophagitis,chronic radioder-matitis and radiation pneumonia had no statistical differences between the two groups (P>0.05).The inci-dence rate of grade Ⅰ-Ⅱ shoulder dysfunction in the VMAT group was lower than that in the IMRT group with statistical difference (P<0.05).No grade Ⅱ and above acute and chronic radiation injury in the two groups occurred.Conclusion VMAT hypofractionated radiotherapy after breast cancer radical operation is safe and effective.

Objective To determine and analyze the content of 45 inorganic elements in Fufang Xiling Jiedu preparation and to provide a reference for the safety detection of Fufang Xiling Jiedu preparation.Methods Inductively coupled plasma mass spectrometry(ICP-MS)was used to ascertain the concentrations of 45 inorganic elements,including Li,B,Al,K,Zn and As from 16 batches of Fufang Xiling Jiedu preparation which were gathered.The content determination findings were plotted as heatmaps,Pearson correlation analysis plot,PCA scatter plots,fingerprints,and control maps.The Pearson correlation analysis and PCA analysis were performed on the content determination results of 16 batches using SPSS 21.0,to evaluate the safety and quality uniformity of Fufang Xiling Jiedu preparation.Results The inorganic elements in Fufang Xiling Jiedu preparation were dominated by K and Ca.The content of different elements in the sample could be categorised into 5 levels.The content of various elements in different batches of Fufang Xiling Jiedu preparation was similar.Pb,Cd,As,Hg and Cu were all within the safety limit as those specified in the Chinese Pharmacopoeia.Co,Y,Sm,Gd,Dy,Th,Al,Si,Fe,Sb and Tl were the characteristic inorganic elements of Fufang Xiling Jiedu preparation.Conclusion This method is easy to operate and suitable for the determination of inorganic elements in Fufang Xiling Jiedu preparation,providing references for the clinical medication safety.

Although the development of COVID-19 vaccines has been a remarkable success, the heterogeneous individual antibody generation and decline over time are unknown and still hard to predict. In this study, blood samples were collected from 163 participants who next received two doses of an inactivated COVID-19 vaccine (CoronaVac®) at a 28-day interval. Using TMT-based proteomics, we identified 1,715 serum and 7,342 peripheral blood mononuclear cells (PBMCs) proteins. We proposed two sets of potential biomarkers (seven from serum, five from PBMCs) at baseline using machine learning, and predicted the individual seropositivity 57 days after vaccination (AUC = 0.87). Based on the four PBMC's potential biomarkers, we predicted the antibody persistence until 180 days after vaccination (AUC = 0.79). Our data highlighted characteristic hematological host responses, including altered lymphocyte migration regulation, neutrophil degranulation, and humoral immune response. This study proposed potential blood-derived protein biomarkers before vaccination for predicting heterogeneous antibody generation and decline after COVID-19 vaccination, shedding light on immunization mechanisms and individual booster shot planning.
Humans ; COVID-19 Vaccines ; Leukocytes, Mononuclear ; Proteomics ; COVID-19/prevention & control* ; Vaccination ; Antibodies ; Antibodies, Viral ; Antibodies, Neutralizing

Objective:To investigate the risk factors and clinical significance of lymph nodes metastasis between sternocleidomastoid and sternohyoid muscle lymph node (LNSS) metastasis in thyroid cancer patients, so as to guide the reasonable dissection of LNSS region and lateral cervical lymph node in patients with papillary thyroid carcinoma (PTC) .Methods:We selected 111 PTC patients with lateral cervical lymph node metastasis who underwent radical thyroidectomy and lateral cervical lymph node dissection from Nov. 2018 to Dec. 2021 in China-Japan Union Hospital of jilin university. All patients were treated with low collar arc incision. Radical thyroidectomy and lateral cervical lymph node dissection were performed according to the guidelines, and lymph nodes in each district were grouped for pathological examination. According to whether LNSS metastasis occurred, they were divided into two groups: LNSS positive group (LNSS metastasis occurred) and LNSS negative group (LNSS metastasis did not happen). We collected the basic information of all 111 PTC patients with lateral lymph node metastasis (LLNM), preoperative color Doppler ultrasound examination and paraffin-embedded pathology and other related clinical case data. Then we described the clinicopathological features of cervical lymph node metastasis. Independent sample t test and Mann-Whitney U test were used for continuous variables, and Fisher exact test was used for data analysis for classified variables. Correlation analysis adopted binary logistics regression model, and analyzed the regularity and risk factors of LNSS metastasis. Results:In this study, the detection rate of LNSS was 64.9% (72/111), the overall LNSS metastasis rate was 7.2% (8/111), and the number of lymph node metastasis was 0-5. Univariate analysis showed that the location of LNSS metastasis was related with the cancer focus ( P<0.001), the preoperative serum thyroglobulin (Tg) level ( P=0.002), the number of lymph node metastasis in lateral cervical level Ⅳ ( P=0.001), the longest diameter of the cancer focus ( P=0.003) and the longest diameter of metastatic lymph nodes ( P=0.001) However, age, sex, whether there is lymph node metastasis in the central region (central lymph node metastasis ,CLNM), and whether there is multifocal cancer were not related to LNSS metastasis ( P≥0.05). Further multivariate analysis and work curve analysis of subjects showed that the tumor located in the lower pole ( P=0.014) and the number of lymph node metastasis in level Ⅳ more than 3 ( P=0.027) were independent risk factors for LNSS metastasis. It was found that the risk of LNSS metastasis increased when the cancer focus was located at the lower pole relative to the upper pole or middle part of the cancer focus ( OR=74.508, 95% CI: 2.373-2339.544). The number of lymph node metastasis in level Ⅳ had a positive effect on LNSS metastasis. The more lymph node metastasis in level Ⅳ, the higher the risk of LNSS metastasis ( OR=1.556; 95% CI=1.051-2.303) . Conclusions:In PTC patients with LLNM, the LNSS metastasis rate was 7.2%, and the advantages of LNSS cleaning outweigh the disadvantages. When the cancer focus is located at the lower pole and the number of lymph node metastasis in region Ⅳ is more than 3, it is necessary to pay attention to the dissection of this group of lymph nodes.

In recent years, the diagnostic radiology, especially CT scanning, has a rapidly increased frequency in our country, becoming the largest artificial radiation source to the average individual doses to the population. In clinical diagnosis and treatment activities, the examined patients and individuals may undergo multiple procedures and multiple frequencies of medical imaging in a short period of time and receive high cumulative radiation doses even exceeding 50 or 100 mSv in a single day, posing a potential risk to their health. Therefore, it is necessary to carry out statistical analysis and management of diagnostic radiation dose information to minimize the probability of excessive dose and associated radiation risk. In this paper, the international cognition of radiation risks in diagnostic radiology, diagnostic equipment and medical imaging frequency, radiation dose and its management status are described. Four countermeasures for radiation dose management are put forward to provide reference for further improving radiation protection in clinical practice.

Objective:To study the healthcare level (HCL) in China and its influencing factors.Methods:By using the data reported in the China statistical yearbook published by the National Bureau of Statistics and in other public literature, HCL was calculated in terms of the number of population and physicians in the whole country and various provinces. Multiple regression was used to analyze the relationship between HCL and regional population, area, number of administrative divisions and gross domestic product (GDP). Pearson correlation analysis was applied to analyze the relationship between healthcare level and medical radiation frequency. Results:Since 2015, Chinese HCL value was lower than 1 000, but there were two provinces with HCL value greater than 1 000 in 2019. Population and GDP were the influencing factors for the HCL, with correlation coefficients of 0.416 and -0.583, respectively. There was a correlation between HCL and medical exposure frequency of Chinese population( r= -0.620, P=0.028). Conclusions:Chinese HCL value was 542 in 2020, but there has been great differences between various provinces. HCL as an indicator of medical exposure assessment needs further research in China.

Objective:To explore the influence of different size related parameters of common CT scanned body parts on body-specific dose estimate (SSDE) , in order to establish rapid conversion factors for SSDE.Methods:A total of 189 clinical cases were collected from 6 common CT scanned body parts, including head, nasal bone, sinus, neck, chest, abdomen and pelvis, at Beijing Tongren Hospital, Capital Medical University from March 8 to May 10, 2021. Batch-processing of image was carried out by using Matlabcode. The axial images′area, anteroposterior (AP) dimension, lateral (LAT) dimension and average CT values were calculated. The conversion factors for estimating body-specific dose values were obtained from the real effective diameter ( De) and water equivalent diameter ( Dw) of the clinical cases, and the differences in values were compared between SSDE ED and SSDE WED. Based on the information on AP, LAT, AP + LAT, estimated De, the real De and Dw obtained in clinical practices, the SSDE rapid correction factors for adult body parts were established. The convenient conversion relation between Dw and De was obtained. Based on the correction factors for Dw, the relative errors of the correction factors for various sizes related parameters were compared. Results:The SSDE fast conversion factors for the real De of the 6 body parts were 1.01, 1.01, 1.01, 0.97, 1.28, 1.32, and those for Dw were 0.87, 0.97, 0.98, 0.99, 1.42, 1.36, respectively. The relative errors of different conversion factors ranged from 0.68% to 18.05%. The conversion factors for abdomen and pelvis had the smallest difference, and those for AP and LAT of the chest had the smallest error. The differences between CTDI vol, SSDE ED and SSDE WED in sinus, chest and abdomen were statistically significant ( tsinus=2.44, 4.23, tchest=17.67, 17.00, tabdomen and pelvis =17.93, 18.75, P<0.05) . The differences between CTDI vol and SSDE WED in head, nasal bone, were statistically significant ( t=-22.27, 2.80, P<0.05) , but not with SSDE ED ( P>0.05) . The difference between CTDI vol and SSDE ED in neck was statistically significant ( t=-3.06, P<0.05) but without statistical insignificance in camparison with SSDE WED ( P>0.05) . Conclusions:SSDE WED can be used to accurately evaluate the body-specific dose estimatates, and different size related parameters can be selected for correction in different scanned body parts. The rapid conversion factor can be easily used in clinical practice to improve the accuracy of estimated radiation dose.

Objective:To analyze the expression of LC3-Ⅱ and ATF3 in hepatocellular carcinoma (HCC) , to explore the relationship between their expression and the prognosis of patients with HCC, and to analyze the expression correlation betweenLC3-Ⅱ and ATF3 in HCC tissues.Methods:Immunohistochemical method was used to detect the expression of LC3-Ⅱ and ATF3 protein in HCC tissue and corresponding paracancerous tissue specimens, to analyze the relationship between these two proteins and the patient's clinicopathological characteristics as well as survival time. Western blot was used to detect the expression of LC3-Ⅱ and ATF3 proteins in fresh HCC tissues and corresponding paracancerous tissue.Results:The expression of LC3-Ⅱ and ATF3 inparacancerous tissues was significantly higher than that in HCC tissues. The expression levels of were related to HCC histopathological grade and venous tumor thrombus (all P<0.05), but were not related to age, gender, and serum alpha-fetoprotein, tumor diameter, HBsAg, etc (all P>0.05) . The low expression of LC3-Ⅱ and ATF3 was significantly related to the poor prognosis of patients with HCC (both P<0.05). Conclusions:Both LC3-Ⅱ and ATF3 protein expression are related to the occurrence and development of HCC. The combined detection of LC3-Ⅱ and ATF3 is helpful for the assessment of the malignant degree of HCC and it is expected to become an important indicator for judging the prognosis of patients.