Objective: To investigate whether membrane vesicles (MVs) of Streptococcus mutans （S.mutans） contain autoinducer-2 (AI-2) and to preliminarily explore the effects of these MVs on the growth and biofilm formation of S. mutans. Methods: MVs were isolated from the S. mutans UA159 strain using differential centrifugation. The isolated MVs were characterized by nanoparticle tracking analysis for particle size and concentration and observed by transmission electron microscopy. The presence of AI-2 was identified using the Vibrio harveyi BB170 bioluminescence assay: the BB170 diluent was supplemented with AB medium (control group), MV extract (MVs group), pre-ultrafiltration supernatant (Sup group), or post-ultrafiltration supernatant (Sup-af group). The effects of MVs on growth and biofilm formation were assessed using the S.mutans UA159 strain or a luxS deletion mutant as the control group, compared with experimental groups stimulated with gradient concentrations of MVs (MVs-2.0E+7, MVs-2.0E+8, and MVs-2.0E+9 groups). Growth curves, MTT assay, and colony-forming unit (CFU) counts were used to determine changes in growth capacity. Biofilm formation was evaluated using crystal violet staining, confocal laser scanning microscopy, and the anthrone method for polysaccharide quantification. Results: Enriched S. mutans MVs were successfully obtained, with an average particle size of approximately 94.19 nm and a concentration of 1.87E+11 particles/mL. The bioluminescence assay showed that the luminescence intensity of the Sup group was higher than that of the Sup-af group, and the MVs group exhibited higher intensity than the control group. Assessments via growth curves, MTT assay, and CFU counts indicated no significant differences in the growth capacity of the various S. mutans strains after treatment with different concentrations of MVs. Crystal violet staining quantification and confocal laser scanning microscopy observations revealed that high-concentration MV treatment (2.0E+9 particles/mL group) resulted in lower biofilm mass compared to the control. The anthrone method showed that the production of both water-soluble and water-insoluble polysaccharides was significantly lower in the high-concentration MV group than in the control. Conclusion S. mutans MVs contain the quorum sensing signal molecule AI-2. These MVs do not significantly affect the growth of S. mutans, but they can regulate biofilm formation and exhibit an inhibitory effect at high concentrations.

Esophageal squamous cell carcinoma is the main histological type of esophageal cancer in China, which seriously threatens the health of people. The application of immunotherapy, mainly immune checkpoint inhibitors, has greatly improved the prognosis of patients with esophageal squamous cell carcinoma, but the efficacy of treatment is still limited. Tertiary lymphoid structure (TLS) is an ectopic organized lymphoid structure that accumulates in non-lymphoid organs. Previous studies have found that TLS in esophageal squamous cell carcinoma is associated with better patient outcomes and enhanced immunotherapy efficacy. Based on current researches about TLS in esophageal squamous cell carcinoma, this paper reviews the relationship between TLS and the prognosis and immunotherapy of patients. We hope to provide reference for the precise immunotherapy of esophageal squamous cell carcinoma.

Background Ozone (O₃) is a major air pollutant. The existing monitoring system has uneven distribution of sites, insufficient coverage in underdeveloped areas, and low temporal resolution, making it difficult to obtain hourly data. This limits the dynamic identification of pollution and the formulation of prevention and control strategies. Objective To construct an hourly O₃ concentration estimation model based on ensemble machine learning, aiming to improve the accuracy of pollution exposure assessment and explore O₃ health impacts. Methods This study integrated land use regression modeling with modern machine learning techniques, employing random forest and XGBoost algorithms to construct base models, and stacking integration using non-negative least squares. The ensemble model was trained and validated across China using high-resolution, multi-source geographic data (e.g., meteorologicaldata, population density, land cover types, and aerosol optical thickness). It was tested in Taiyuan City, combined with a distributed lag non-linear model to analyze the association between O₃ and emergency admissions. Results The constructed ensemble model performed well in predicting O₃ concentration, with a higher coefficient of determination (R²) and a lower root-mean-square deviation (RMSE) compared to the single models. The R² improved from 0.90 to 0.92, and the RMSE decreased from 11.41 to 10.62, enhancing both prediction accuracy and generalization ability. In the application to Taiyuan City, the model successfully imputed the hourly-level data for the entire year. The distributed lag non-linear model analysis revealed that the relative risk (RR) values for the 6th to 8th days following O₃ exposure were 1.14 (95%CI: 1.01, 1.29), 1.16 (95%CI: 1.02, 1.31), and 1.14 (95%CI: 1.01, 1.29), respectively, which were significantly higher than 1, indicating a significant lagged association (lagged 6-8 d) between O₃ and the number of emergency room visits. Conclusion A high-precision, hourly-level O₃ concentration estimation model is successfully constructed by combining the land use regression model with an ensemble machine learning approach to provide a scientific basis for environmental policy formulation and public health intervention. The application of the model verifies its generalization ability and practical application value, which can provide a new technical framework for subsequent environmental health research.

This study aimed to systematically construct a transitional curriculum for newly recruited surgical residents and to evaluate its preliminary application outcomes through pre and postimplementation assessments, so as to provide practical references for the design and dissemination of such curricula.

ObjectiveTo understand the distribution of enrofloxacin (ENR) residues in freshwater fish, to evaluate the dietary exposure risk to ENR for consumers through the consumption of different freshwater fish in Shanghai, and to provide a reference for controlling antibiotic residues in freshwater fish. MethodsGrass carp, Wuchang bream, pond loach, and Asian swamp eels were purchased from the markets in Shanghai. After being fed with ENR, the fish were divided into 42 batches according to their species and weight, and thereafter ENR residues in the muscles and skin of the fish were measured. In addition, a total of 44 batches of Wuchang bream, pond loach, Asian swamp eels were purchased from the markets, and the ENR residues in the muscles with or without the fish skin were measured, and the exposure risk was evaluated. ResultsThe average residues of ENR in skin of the freshwater fish after being fed with drugs in the 42 groups were higher than those in muscles (M=659.38 μg·kg^-1, M=460.83 μg·kg^-1; z=-2.212, P=0.027). The over-standard rates of ENR residues in the muscles with or without skin 44 batches of freshwater fish of sold in Shanghai were 36.36% and 29.55%, respectively. The median exposure, P₉₅ exposure, and maximum exposure to ENR through the consumption of the muscles with the skin for adults and children in Shanghai were higher than those through the consumption of muscles without the skin. For children, the margin of safety (MOS) for the max exposure to ENR by consuming the muscles with the skin was more than 1, while the MOS was less than 1 in all other cases for both children and adults. ConclusionThe ENR residues in the skin of freshwater fish are generally higher than those in the muscles. The risk of ENR residues in freshwater fish sold in Shanghai is within a controllable range. However, there might be a certain risk of acute exposure to ENR for children by consuming muscles with the skin of freshwater fish.

According to the theory of "toxin accumulation damaging yin"， the accumulation of pathological products and the disruption of homeostasis in the pre-metastatic niche （PMN） of malignant tumors correspond to "toxin accumulation" and "yin damage" respectively. During the dynamic evolution of PMN， the main pathogenesis in the initial stage is healthy qi deficiency and phlegm congestion， obstruction in the ying （营） and wei （卫） level， for which the therapeutic approach is fortifying spleen and warming yang， reinforcing healthy qi， consolidating the root， and assissting in resolving phlegm. In the progression stage， the predominant mechanism is mutual binding of phlegm and stasis， with collateral damage and pathological transformation. Treatment should focus on resolving phlegm and eliminating stasis， using insect-derived medicinals to attack accumulation and block pathological transmission. In the terminal stage， the main pathogenesis involves phlegm-stasis transforming into fire， with depletion of qi and yin， for which it is suggested to replenish qi and nourish yin， combine clearing and tonifying methods to control fire-toxin. After the PMN has formed， pathogenic toxin may flow along the collaterals， tending to lodge in corresponding viscera with functional imbalance and deviation between deficiency and excess， eventually giving rise to malignant tumors. Understanding the pathogenesis of the PMN in the malignant tumors based on the "toxin accumulation damaging yin" theory may provide a valuable perspective for developing traditional Chinese medicine strategies for the prevention and treatment of tumor metastasis.

Objective:To explore the predictive value of very low frequency (VLF) for the efficacy of vitamin D treatment in children with postural orthostatic tachycardia syndrome (POTS).Methods:A retrospective case-control study was conducted. A total of 65 POTS children from the Department of Pediatrics of the Second Hospital of Lanzhou University from November 2023 to May 2024 were selected as the research subjects, while 102 healthy children from the same period were selected as the control group. The 25 (OH) D levels between POTS children and healthy children were compared. The frequency of eight main symptoms, including palpitations, headache, cold sweat, blurred vision, chest tightness, dizziness, fainting, and digestive discomfort in the POTS group were analyzed, the symptom scores of the orthostatic intolerance were calculated, and the parameters related to short-range heart rate variability (HRV) during the upright test, head-up tilt test (HUTT) were collected. The correlation between 25 (OH) D levels and symptom scores of orthostatic intolerance symptoms and HRV parameters in children with POTS were analyzed by Pearson correlation analysis. The total symptom scores of children with POTS were compared for 3 months before treatment and 2 months after treatment with vitamin D 800 U/d. The difference in score before and after treatment was ≥2 as responsive group, and the score difference before and after treatment was <2 as non-responsive group. The demographic characteristics including age, gender, height, weight, body mass index, as well as HRV parameters such as the standard deviation of nn intervals (SDNN), the standard deviation of the average NN intervals (SDANN), the root mean square of successive differences (rMSSD), low-frequency (LF), high-frequency (HF), very-low-frequency (VLF) were compared between the responsive group and non-responsive group. Multivariate Logistic regression was analyzed to screen independent influencing factors of vitamin D treatment efficacy for POTS. The marker molecules related to the efficacy of vitamin D treatment in children with POTS were analyzed through receiver operating characteristic (ROC) curve.Results:A total of 167 children were included in this study. There were 65 children in the POTS group, 38 males and 27 females, with the age of (10.6±2.2) years. There were 102 healthy children in the control group, 53 males and 49 females, with the age of (11.2±1.8) years.There was no statistically significant difference in gender and age between the two groups (both P>0.05). The serum 25 (OH) D level in children in the POTS group was (37±18)nmol/L, lower than that in the control group (61±17)nmol/L ( P<0.05).Pearson correlation analysis showed that serum 25(OH)D was positively correlated with VLF, SDNN and HF ( r=0.43, 0.65, 0.36, respectively, all P<0.05). Among the POTS children, there were 48 cases in responsive group and 17 cases in non-responsive group. Univariate analysis revealed that responsive group exhibited significantly lower values in age, SDNN, SDANN, and VLF compared to the non-responsive group (all P<0.05). Multivariate Logistic regression analysis showed that age ( OR=1.47, 95% CI 1.08-2.01), SDNN ( OR=1.01, 95% CI 1.00-1.22) and VLF ( OR=1.01, 95% CI 1.00-1.15) were independent influencing factors in the effect of vitamin D in POTS children (all P<0.05). ROC curve analysis showed that the area under the curve of VLF predicting response to vitamin D treatment for POTS was 0.72 (95% CI 0.58-0.85, P=0.008). When the cutoff value was 1 272 ms 2, the sensitivity and specificity were both 70%. Conclusion:VLF may help predict the efficacy of vitamin D treatment in children with POTS.

There exist risks of ionizing radiation in radiodiagnosis examinations. Implementing shielding protection following the optimization and as low as reasonably achievable (ALARA) principles represents a measure to reduce radiation doses to patients. The implementation of shielding protection in clinical practices should meet high requirements due to variations in the modalities and items in radiodiagnosis examinations, the characteristics and irradiation method of X-ray beams, the method of automatic selection of image quality and radiation dose-related parameters by imaging equipment, the radiation sensitivity of human tissues and organs. This review introduced the shielding products, methods and effects in various radiodiagnosis examinations, as well as the current status and challenges in their applications, aiming to provide a reference for future related research and clinical practices.

Venous system diseases mainly include varicose veins and venous malformations of lower limbs and the genital system. Most of them are chronic diseases that cause serious clinical symptoms to patients and affect their health and quality of life. Sclerotherapy has become the first-line therapy for venous system diseases. However, there are problems such as incomplete fibrosis and vascular recanalization after sclerotherapy, and improper operation will cause serious adverse consequences. Therefore, exploring a safe and effective sclerotherapy strategy is essential for developing clinically successful sclerotherapy. To solve the above problems, we proposed a new sclerotherapy strategy with a dual mechanism of "vascular damage and plasmin (PLA) system inhibition." We intended to construct a novel cationic surfactant (AEO_x-TA) by reacting tranexamic acid (TA), a parent structure, with fatty alcohol polyoxyethylene ether (AEO_x) by ester bonds. AEO_x-TA could damage vascular endothelium and initiate a coagulation cascade effect to induce thrombus. Furthermore, AEO_x-TA could be degraded by esterase and release the parent drug, TA, which could inhibit the PLA system to inhibit the degradation of thrombus and extracellular matrix and promote the process of vascular fibrosis. In addition, such surfactant-based sclerosants have foam-forming properties, and they can be blended with polyvinyl alcohol (PVA) to prepare a highly stable foam formulation (AEO_x-TA/P), which can achieve a precise drug delivery and prolonged drug retention time, thereby improving drug efficacy and reducing the risk of ectopic embolism. Overall, the novel cationic surfactant AEO_x-TA provides a new avenue to resolve the bottleneck: surfactant sclerosants' efficiency is relatively low in the current sclerotherapy.