Objective:To explore the dosimetry optimization strategy based on filter thickness and shape selection for the bulb superficial X-ray radiotherapy unit.Methods:Monte Carlo code TOPAS was used to model tubular equipment, and the dose distribution from six X-ray energies (50-150 kV) and five conventional aluminum filters (0.5-3.0 mm) with different thickness were simulated in the water model. The percentage depth dose (PDD) curve along the central axis, the center-axis profile dose at different depths, and the lateral dose distribution were analyzed. The dose distribution of three different designs of aluminum filters (conventional cylindrical, conical and oblique cylindrical filters) was compared to evaluate the effect of dosimetric optimization of different filter shapes.Results:Under the same energy, increasing the thickness of the filter can optimize the superficial skin dose, and the optimization effect of depth dose uniformity can be increased by 26% at a depth of 5.5 mm at 70 kV energy. The raised, flat and inclined dose distribution modes can be achieved by using conventional cylindrical, conical and inclined aluminum filters.Conclusions:By selecting the appropriate X-ray energy and filter thickness, an ideal dose distribution matching the tumor depth can be achieved. The application of personalized filters is also of great significance for diverse target areas.

Objective:To investigate the application of the conjugate gradient (CG) algorithm to treatment plan optimization for intensity-modulated brachytherapy (IMBT).Methods:The general Monte Carlo software TOPAS was utilized to simulate the 192Ir source of IMBT, and the unit dose contribution matrix was calculated. An objective function was established using the weighted least squares method and was solved using the CG algorithm to achieve optimized IMBT treatment plans. The optimization was validated using five clinical cervical cancer cases under modulation width 60°. The dose distributions of IMBT treatment plans under 45°, 60°, 90°, 120°, and 180° modulation widths were compared using the Wilcoxon test to determine the optimal IMBT treatment plan for cervical cancer treatment. Results:The CG algorithm successfully optimized IMBT treatment plans under modulation width 60° for five cases within 22.2 s on average. On the premise of sufficient target dose coverage, the average D2 cm 3 values of the bladder and rectum in IMBT treatment plans were 3.66 and 1.97 Gy, respectively, representing reductions of 0.54 and 0.69 Gy compared to traditional brachytherapy plans. For the five modulation widths, the D90% values of all IMBT treatment plans reached 6 Gy, without statistically significant differences ( P > 0.05). The average D2 cm 3 values of the bladder in IMBT treatment plans were significantly lower than those in the traditional brachytherapy plans( P<0.05), with modulation width 60° associated with the greatest reduction of 0.61 Gy. In contrast, the average D2 cm 3 values of the rectum under 45°, 60°, and 90° modulation widths decreased by 0.63, 0.54, and 0.45 Gy, respectively, compared to traditional plans, with statistically significant differences( P<0.05). Conclusions:The CG method enables rapid achievement of optimized IMBT treatment plans that meet clinical requirements, and modulation width 60° contributes to valid dosimetric optimization. This study can serve as a guide for the clinical implementation of IMBT.

Malignant tumors are one of the major diseases that endanger human life and health. Chinese medicine has unique advantages in clinical anti-tumor treatment. However， how to translate the anti-tumor effects of Chinese medicine into clinical practice is the core issue that must be addressed in the process of treating malignant tumors with traditional Chinese medicine （TCM）. Unlike modern chemical drugs， the compatibility application of Chinese medicine is the key factor that determines whether Chinese medicine can achieve optimal anti-tumor efficacy and realize the goal of "enhancing efficacy and reducing toxicity". The formulation structure based on this compatibility is the basic form for the safe， efficient， and rational clinical use of anti-tumor Chinese medicine， and it mainly includes three categories： herb pairs， tri-herbal combinations， and compound compatibility. Although herb pairs have the characteristics of a simple structure and strong targeting （enhancing efficacy and reducing toxicity）， they often have a single effect and cannot fully address the complex pathogenesis of tumors. As a result， herb pairs are rarely used alone in practice. Compared to herb pairs， tri-herbal combinations broaden the application scope of herbs in clinical treatment， but their therapeutic range remains limited. The traditional "sovereign， minister， assistant， and guide" compound prescription， which includes herb pairs and tri-herbal combinations， improves the efficacy of herbs in treating serious diseases， hypochondriasis， chronic diseases， and miscellaneous disorders. However， due to the limitations of its historical background， it has not been integrated with modern clinical practice and modern pharmacological research， which restricts the development of compound compatibility theory. With the emergence of modern medical technology， it has been combined with traditional compatibility theory of Chinese medicine to create an innovative modern compatibility theory. This includes the "aid medicine" theory derived from modern Chinese medicine pharmacology， which compensates for the inability of the "sovereign， minister， assistant， and guide" theory to accurately apply medicine. Additionally， the "state-targeted treatment based on syndrome differentiation" theory， developed from pharmacology and modern medicine， addresses the deficiency in disease cognition in the "sovereign， minister， assistant， and guide" theory. Under the guidance of these compatibility forms and theories， clinical anti-tumor Chinese medicine can exert its maximum anti-tumor efficacy， which is of great significance for the application of Chinese medicine in clinical tumor treatment.

Functional constipation is a common functional gastrointestinal disorder with a multifactorial and incompletely understood pathogenesis.Recent studies have revealed that its development involves the interplay of multiple mechanisms,including neurogenic and myogenic dysfunction of the colon,reduction and impairment of interstitial cells of Cajal(ICCs),outlet obstruction,dysregulation of the gut-brain axis,immune activation,and gut microbiota imbalance.Slow-transit constipation is mainly associated with enteric neural abnormalities,disruption of ICC signaling,and inflammation,whereas outlet obstruction constipation often results from pelvic floor dysfunction and rectal hyposensitivity.Dysregulation of the gut-brain axis plays a central role,involving impaired central regulation,hormonal imbalance,and enhanced local immune response.Additionally,gut microbial metabolites such as short-chain fatty acids,bile acids,and methane affect colonic motility and inflammation.This review summarizes the current understanding and research progress on the pathogenesis of functional constipation,providing insights for mechanism-based and individualized therapeutic approaches.

Objective:To investigate and validate the performance of a dosiomics model that utilized 3D dose distribution to forecast radiation-induced temporal lobe injury (RTLI) in nasopharyngeal carcinoma (NPC) patients following intensity-modulated radiotherapy (IMRT).Methods:Clinical data of 3578 patients diagnosed with NPC admitted to Jiangsu Cancer Hospital from January 2011 to December 2021 were retrospectively analyzed. According to the inclusion and exclusion criteria, 97 NPC patients who developed RTLI were assigned into the case group. A 1:1 propensity score matching (PSM) method was used to match 97 NPC patients without RTLI as the control group. Patients were assigned into the training cohort ( n=135) and the validation cohort ( n=59) at a 7:3 ratio by simple random method. Dosiomics features were extracted from the patients' three-dimensional dose distribution maps. Spearman rho and the least absolute shrinkage and selection operator regression were used to select dosiomics features. Clinical features were collected and screened by univariate and multivariate analyses. Eight machine learning classifiers were then trained to build dosiomics models and clinical models, respectively. The area under the ROC curve (AUC), sensitivity, and specificity were calculated to compare the predictive performance of the dosiomics and clinical models. Multivariate analysis was conducted using logistic regression to assess the influencing factors, while comparisons of the ROC curves between two different models were performed using the DeLong test. Results:A total of 1130 dosiomics features were extracted from the three-dimensional dose distribution maps, and 14 features were retained for model building after feature selection. The model based on the support vector machine (SVM) classifier achieved the highest AUC value of 0.977 (95% CI: 0.949-1.000) in the validation cohort, with an AUC of 1.000 (95% CI: 1.000-1.000) in the training cohort. By conducting univariate and multivariate analyses of the patients' clinical features, 2 clinical features were retained to build the clinical model. The model based on the SVM classifier achieved the optimal AUC value of 0.667 (95% CI: 0.523-0.810) in the validation cohort, with an AUC of 0.804 (95% CI: 0.730-0.878) in the training cohort. DeLong test showed that the difference between the dosiomics and clinical models was statistically significant ( P<0.05). Conclusion:The dosiomics model based on 3D dose distribution yields high predictive performance for RTLI in NPC patients after IMRT, which surpasses the clinical feature model, providing a new approach for early clinical prediction of RTLI.

Due to advances in treatment methods, the survival rate and quality of life of cancer patients have been improved. Radiation-induced vascular injury (RIVI) is a common adverse reaction following radiotherapy, mainly manifested as capillary injury and atherosclerosis in the irradiated area. Radiotherapy induces RIVI in the cerebral vessels, carotid arteries, coronary arteries, and large arteries through mechanisms such as endothelial cell injury and senescence, oxidative stress and inflammatory responses, angiogenesis, and vascular remodeling. In this review research progress in the pathological features, pathophysiological mechanisms, clinical manifestations, prevention and treatment strategies of RIVI was summarized, aiming to provide insights for future research on RIVI.

Objective To investigate the technical capacity and service quality of occupational health technical service institutions (hereinafter referred to as "occupational health institutions") in Guangdong Province. Methods All occupational health institutions in Guangdong Province that had valid occupational health service qualifications and within the validity period were included for analysis. Data on basic information, employed personnel, and results of professional technical capacity assessments across occupational health institutions were obtained through the Guangdong Provincial Occupational Health Technical Quality Control Center. Results A total of 99 institutions with 2 732 technical staff were included in this study. Occupational health institutions in Guangdong Province were mainly distributed in the Pearl River Delta region, accounting for 87.9% (87/99) of the total. The number of public and private health institutions was 23 and 76, accounted for 23.2% and 76.8% respectively. In terms of technical personnel, the percentage of individuals worked in public or private health institutions was 24.1% and 75.9%, respectively. Personnel titles were predominantly intermediate level and no title, accounting for 38.7% and 26.4%, respectively. Individuals with a bachelor′s degree or above accounted for 67.4%. Engineering and other professionals accounted for 35.4% and 30.5%, respectively. Private institutions undertook 97.3% of testing and evaluation workload related to occupational hazard in the province. The number of occupational health institutes acquiring category Ⅰ and Ⅱ service license were 97 and 13. Among institutions participating in inter-laboratory comparisons, the overall pass rates for quantitative items were 95.5% in public and 70.3% in private institutions, while the pass rates for qualitative items were 100.0% and 94.5%, respectively. Conclusion Occupational health institutions in Guangdong Province face issues such as imbalanced regional distribution, uneven development, and insufficient technical competence and testing capacity of professional personnel. Health authorities at all levels should continue to strengthen supervision and quality control to solidify the technical foundation and comprehensively enhance service capacity and quality.

Objective To investigate an automated pretreatment technology for detecting levels of free silica in workplace dust. Methods An fully automated pretreatment workstation for detecting free silica levels in workplace dust was developed by integrating graphite-controlled digestion temperature, online-controlled dilution of digestion solutions, and filtration endpoint recognition based on monitoring technology, combined with multi-channel synchronous measurements. Results The fully automatic pretreatment workstation was used to digest and filter 14 standard samples of free silica produced by three institutions, and then detected by pyrophosphate method. The result range of high-, medium-, and low-level free silica standard samples detection was 66.5%-84.8%, 40.0%-44.5%, and 2.1%-24.8%, respectively. The mean relative standard deviations were 3.9%, 1.4% and 1.5%. Conclusion The fully automated pretreatment workstation produced results that met relevant requirements. It can effectively replace the manual digestion and filtration steps of the pyrophosphate method to measure free silica levels in workplace dust and enable rapid detection of free silica in dust samples.

Single-molecule immunoassay is a "digital" immunodetection method that confines immune complexes within an extremely small volume, achieving absolute signal quantification. With a lower detection limit reaching femtograms per milliliter (fg/ml), it offers high sensitivity. This technology is suitable for precision medical testing, facilitating rapid and accurate quantification of low-abundance substances in patient blood samples. At present, single-molecule immunoassay has demonstrated significant application values in the fields of neurodegenerative diseases, cancers, infectious diseases, and cardiovascular diseases. However, it still faces challenges in clinical applications, such as high costs and operational complexity. In the future, further researches are needed to braoden the applications of single-molecule immunoassay to other disease areas. Meanwhile, as this technology progresses into clinical laboratories, it is imperative to improve the interpretation of testing results, clinical validation, and the standardization of testing procedures.

Objective:To explore the dosimetry optimization strategy based on filter thickness and shape selection for the bulb superficial X-ray radiotherapy unit.Methods:Monte Carlo code TOPAS was used to model tubular equipment, and the dose distribution from six X-ray energies (50-150 kV) and five conventional aluminum filters (0.5-3.0 mm) with different thickness were simulated in the water model. The percentage depth dose (PDD) curve along the central axis, the center-axis profile dose at different depths, and the lateral dose distribution were analyzed. The dose distribution of three different designs of aluminum filters (conventional cylindrical, conical and oblique cylindrical filters) was compared to evaluate the effect of dosimetric optimization of different filter shapes.Results:Under the same energy, increasing the thickness of the filter can optimize the superficial skin dose, and the optimization effect of depth dose uniformity can be increased by 26% at a depth of 5.5 mm at 70 kV energy. The raised, flat and inclined dose distribution modes can be achieved by using conventional cylindrical, conical and inclined aluminum filters.Conclusions:By selecting the appropriate X-ray energy and filter thickness, an ideal dose distribution matching the tumor depth can be achieved. The application of personalized filters is also of great significance for diverse target areas.