Objective To investigate the effects and underlying mechanisms of a spray prepared from exosomes derived from M2 macrophages induced by interleukin-4 （IL-4） and tantalum particles （Ta） on the healing of pressure ulcers. Methods Bone marrow-derived macrophages were polarized into M2 macrophages using IL-4 or Ta, and exosomes （Exo-IL-4/Exo-Ta） were extracted. The regulatory effects of Exo-IL-4/Exo-Ta on M1 macrophage phenotypes and fibroblast matrix secretion were evaluated in vitro. Proteomic analysis was conducted to explore the biological processes and regulatory networks associated with Exo-Ta. A rat pressure ulcer model was used to assess the effects of Exo-IL-4/Exo-Ta spray on wound healing rate, inflammatory cell infiltration, and collagen deposition. Results In vitro, Exo-IL-4/Exo-Ta induced the polarization of M1 macrophages to M2 macrophages, reduced the secretion of pro-inflammatory factors, and promoted the expression of anti-inflammatory substances. Additionally, Exo-IL-4/Exo-Ta enhanced the production of collagen and fibronectin in fibroblasts. Proteomic analysis revealed that Exo-Ta primarily participated in biological processes such as energy metabolism and macromolecule biosynthesis. In vivo, Exo-IL-4/Exo-Ta spray accelerated wound healing, reduced inflammatory infiltration, and improved tissue remodeling in the rat pressure ulcer model. Conclusion Exosome sprays derived from M2 macrophages could accelerate pressure ulcer healing by modulating inflammation and promoting tissue regeneration, which demonstrated excellent clinical application potential.

Objective:To investigate the relationship between plasma fluoride content, daily calcium intake and blood cell parameters in children and adolescents.Methods:This study was based on the National Health and Nutrition Examination Survey (NHANES) database of the United States from 2013 to 2016, with 3 684 children and adolescents aged 6 - 19 as the research subjects. Information on plasma fluoride content, daily calcium intake and blood cell parameters from the database were collected. Non-linear relationships between plasma fluoride content, daily calcium intake and blood cell parameters were analyzed using restricted cubic splines. If there was a non-linear relationship, the optimal inflection point was calculated using threshold/saturation effect analysis method. Subsequently, multiple linear regression models were used to analyze the associations among the three, and the modification effect of daily calcium intake (binary classification, stratified by median daily calcium intake) on the association between plasma fluoride content and blood cell parameters was analyzed.Results:There was no non-linear relationship between plasma fluoride content and white blood cell count, hemoglobin content and platelet count ( Pnon-linear > 0.05), but there was a non-linear relationship between plasma fluoride content and erythrocyte count and hematocrit ( Pnon-linear < 0.001). After adjusting for confounding factors, the optimal inflection points of the effects of plasma fluoride content on erythrocyte count and hematocrit were 0.54 and 0.31 μmol/L, respectively. There was no non-linear relationship between daily calcium intake and blood cell parameters ( Pnon-linear > 0.05). After adjusting for confounding factors, for every 1 μmol/L increase in plasma fluoride content, the white blood cell count increased by 0.49 × 10 9/L ( P = 0.009). There was a saturation effect in the association between plasma fluoride content, erythrocyte count and hematocrit: when plasma fluoride content was < 0.54 μmol/L, the erythrocyte count decreased by 0.46 × 10 12/L for every 1 μmol/L increase ( P < 0.001). When plasma fluoride content was < 0.31 μmol/L, the hematocrit decreased by 6.29% for every 1 μmol/L increase ( P = 0.006). The above associations were not statistically significant when plasma fluoride content was higher than the optimal inflection points ( P > 0.05). After stratification according to the median daily calcium intake, in the low-calcium group (daily calcium intake < 0.87 g), for every 1 μmol/L increase in plasma fluoride content, the white blood cell count increased by 0.77 × 10 9/L ( P = 0.001). When plasma fluoride content was < 0.54 μmol/L, the erythrocyte count decreased by 0.41 × 10 12/L for every 1 μmol/L increase ( P = 0.002). When plasma fluoride content was ≥0.54 μmol/L, erythrocyte count decreased by 0.47 × 10 12/L for every 1 μmol/L increase ( P < 0.001). When the plasma fluoride content was < 0.31 μmol/L, the hematocrit decreased by 8.29% for every 1 μmol/L increase ( P = 0.011). The above associations were not statistically significant in the high-calcium group (daily calcium intake ≥0.87 g, P > 0.05). There was an interaction of daily calcium intake and plasma fluoride content on platelet count ( Pinteraction = 0.070), as demonstrated by an increase in platelet count of 12.68 × 10 9/L ( P = 0.013) in the low-calcium group and a decrease in platelet count of 9.05 × 10 9/L ( P = 0.035) in the high-calcium group for every 1 μmol/L increase in plasma fluoride content. Conclusions:The blood cell parameters of children and adolescents are closely related to plasma fluoride content, but not directly related to daily calcium intake. However, the correlation between plasma fluoride content and blood cell parameters varies among different calcium intake populations, and daily calcium intake can modify the association between plasma fluoride content and platelet count.

Objective:To study the feasibility of magnetic resonance imaging(MRI)technique with amide proton transfer(APT)in predicting the prognosis of cerebral stroke.Methods:A total of 71 patients with acute cerebral stroke who admitted to the Nanjing First Hospital,Nanjing Medical University from September 2022 to May 2023 were selected.All of them underwent the test of National Institute of Health Stroke Scale(NIHSS),and received the MRI examination with chemical exchange saturation transfer(CEST).According to the modified Rankin scale(mRS)values of 1-month follow-up,they were divided into favorable recovery group(mRS<2,44 cases)and poor group(mRS≥2,27 cases).The asymmetric magnetization transfer ratio(MTRasym)image(APT)was obtained by analyzing data with special software.And then,the difference(△APTw)of APT values between ischemic zone and contralateral normal tissue was further calculated.The △APTw values of two groups were compared and analyzed,and the Pearson correlation analysis was adopted to analyze the correlation among △APTw,NIHSS and mRS.The receiver operating characteristics(ROC)curve was drawn,and the area under curve(AUC)of ROC curve was calculated.Results:There were significant positive correlations among △APTw,NIHSS and mRS scores(R2=0.659,0.522,P<0.001),and the differences of △APTW,NIHSS and mRS scores between the favorable recovery group and poor group were significant(t=5.73,6.36,13.92,P<0.05),respectively.The AUC value was 0.886,and the sensitivity and specificity of prediction were respectively 77.8%and 95.5%.The positive and negative predictive values were respectively 91.3%and 87.5%.Conclusion:APT imaging technique has feasibility in predicting the prognosis of acute cerebral ischemic stroke.

Objective:Analyze the operation mode of the valuation investment of scientific and technological achievements in hospitals, and provide a certain reference for other hospitals to carry out valuation investment in scientific and technological achievements.Methods:This paper analyzed the origin and current situation of the valuation investment of scientific and technological achievements. Taking Peking University Cancer Hospital as an example, it made an in-depth analysis of the valuation investment model of scientific and technological achievements.Results:The study found that the valuation investment of scientific and technological achievements in hospitals includes several key links such as signing the Valuation Investment Agreement, signing the Shareholder Agreement and the Articles of Association, the registration and identification of technical contracts, the issuance of invoices, and deferred taxation. And several suggestions on how to apply this model for the transformation of scientific and technological achievements were put forward.Conclusions:Although the implementation process of scientific and technological achievements is cumbersome, the operation mode is diverse, and the ownership of equity is difficult to distinguish, the advantages are extremely obvious. It can closely combine technological capital and industrial capital, form a strong and effective technological alliance and a community of multiple interests, better use the market-oriented motivation of scientific and technological innovation, and carry out cutting-edge research in line with market prospects.

Objective:We aimed to develop a novel visualized model based on nomogram to predict postoperative overall survival.Methods:This was a multicenter, retrospective, observational cohort study, including participants with histologically confirmed gastric and colorectal cancer who underwent radical surgery from 11 medical centers in China from August 1, 2015 to June 30, 2018. Baseline characteristics, histopathological data and nutritional status, as assessed using Nutrition Risk Screening 2002 (NRS 2002) score and the scored Patient-Generated Subjective Global Assessment, were collected. The least absolute shrinkage and selection operator regression and Cox regression were used to identify variables to be included in the predictive model. Internal and external validations were performed.Results:There were 681 and 127 patients in the training and validation cohorts, respectively. A total of 188 deaths were observed over a median follow-up period of 59 (range: 58 to 60) months. Two independent predictors of NRS 2002 and Tumor-Node-Metastasis (TNM) stage were identified and incorporated into the prediction nomogram model together with the factor of age. The model's concordance index for 1-, 3- and 5-year overall survival was 0.696, 0.724, and 0.738 in the training cohort and 0.801, 0.812, and 0.793 in the validation cohort, respectively.Conclusions:In this study, a new nomogram prediction model based on NRS 2002 score was developed and validated for predicting the overall postoperative survival of patients with gastric colorectal cancer. This model has good differentiation, calibration and clinical practicability in predicting the long-term survival rate of patients with gastrointestinal cancer after radical surgery.

Hyperbranched polymers (HBPs) have drawn great interest in the biomedical field on account of their special morphology, low viscosity, self-regulation, and facile preparation methods. Moreover, their large intramolecular cavities, high biocompatibility, biodegradability, and targeting properties render them very suitable for anti-tumor drug delivery. Recently, exploiting the specific characteristics of the tumor microenvironment, a range of multifunctional HBPs responsive to the tumor microenvironment have emerged. By further introducing various types of drugs through physical embedding or chemical coupling, the resulting HBPs based delivery systems have played a crucial part in improving drug stability, increasing effective drug concentration, decreasing drug toxicity and side effects, and enhancing anti-tumor effect. Here, based on different types of tumor microenvironment stimulation signals such as pH, redox, temperature, etc., we systematically review the preparation and response mechanism of HBPs, summarize the latest advances in drug delivery applications, and analyze the challenges and future research directions for such nanomaterials in biomedical clinical applications.

Objective To investigate the effect of exposure to lead oxide nanoparticles (PbO NPs) on the polarization of microglia in mouse hippocampus. Methods i) Specific pathogen-free male C57 mice were randomly divided into control group, low-, medium- and high-dose groups, with 10 mice in each group. Mice in these three dose groups were intraperitoneally injected with PbO NPs suspension at doses of 5, 10 and 20 mg/kg per day, respectively, and mice in the control group were intraperitoneally injected with the same volume of 0.9% sodium chloride solution, five days per week for four weeks. ii) BV-2 cells were treated with PbO NPs at doses of 0.0, 2.5, 5.0 and 10.0 mg/L for 24 hours. iii) BV-2 cells were randomly divided into control group, PbO NPs group and triggering receptor expressed on myeloid cells 2 (TREM2) high expression + PbO NPs group. The cells in the control group received no treatment. The cells in PbO NPs group were exposed to 10.0 mg/L PbO NPs suspension for 24 hours. Cells in TREM2 high expression + PbO NPs group were transfected with Trem2 high expression plasmid, and then exposed to 10.0 mg/L PbO NPs suspension for 24 hours. iv) The mRNA expression of M1 markers ［nitric oxide synthase (iNos), cyclooxygenase 2 (Cox2), chemokine receptor 7 (Ccr7)］, M2 markers ［arginin-1 (Arg-1), transforming growth factor-β (Tgf-β), chemokine receptor 2 (Ccr2)］ and Trem2 of microglia was detected by real-time fluorescent quantitative polymerase chain reaction. The protein expression of iNOS, ARG-1 and TREM2 was detected by Western blotting. Results i) During the experiment, there was no significant difference in body weight of mice among these four groups (P>0.05). The relative expression of Cox2 and Ccr7 mRNA in the hippocampus of the mice increased in the low-dose group and the iNos, Cox2 and Ccr7 mRNA increased in the medium- and high-dose groups, compared with the control group (all P<0.05). The relative mRNA expression of Tgf-β in the hippocampus of the mice of low-dose group and Arg-1, Tgf-β and Ccr2 in the medium- and high-dose groups was decreased compared with the control group (all P<0.05). The mRNA relative expression of iNos, Cox2 and Ccr7 was increased (all P<0.05), while the mRNA relative expression of Arg-1, Tgf-β and Ccr2 was decreased (all P<0.05) in the hippocampus of the mice of high-dose group compared with the low-dose group. The relative expression of Trem2 mRNA and TREM2 protein in the hippocampus of mice of the medium- and high-dose groups was lower than those in the control group (all P<0.05). The relative expression of Trem2 mRNA and TREM2 protein in the hippocampus of mice of the high dose group was lower than those in the low- and the medium-dose groups (all P<0.05). With the increase of PbO NPs exposure dose, the relative expression of iNOS protein in hippocampus tissues of mice increased (P<0.01), and the relative expression of ARG-1 protein decreased (P<0.01). ii) With the increase of PbO NPs exposure dose, the relative expression of iNOS protein increased (P<0.01), and the relative expression of ARG-1 protein decreased (P<0.01) in BV-2 cells. The relative expression of iNOS protein in BV-2 cells of PbO NPs group and TREM2 high expression + PbO NPs group was increased (all P<0.05), and the relative expression of ARG-1 protein decreased (all P<0.05) compared with the control group. The relative expression of iNOS protein decreased (P<0.05), and the relative expression of ARG-1 protein increased (P<0.05) in BV-2 cells of TREM2 high expression + PbO NPs group compared with the PbO NPs group. Conclusion Exposure to PbO NPs could increase the M1 polarization and decrease the M2 polarization of microglia, with a dose-effect relationship. The M1 polarization of microglia decreased and M2 polarization increased after overexpression of Trem2 gene. The regulation of microglia polarization by TREM2 may be involved in the neurotoxic effects of PbO NPs.

ObjectiveTo explore the application value of CT pulmonary angiography (CTPA) in assessing the severity of acute pulmonary embolism (APE) and right heart function in rehabilitation patients. MethodsFrom January, 2013 to January, 2020, 133 inpatients (94 positive and 39 negative) who underwent CTPA examination in Beijing Bo'ai Hospital were involved. Positive patients were further divided into mild, moderate and severe groups based on the pulmonary artery obstruction index (PAOI). The clinical parameters and right heart function indicators were compared. Spearman correlation analysis was used to analyze the correlation between PAOI, and clinical parameters and right heart function indicators, and Logistic regression analysis was used to predict the risk factors of APE. ResultsThere was significant difference in lower extremity venous thrombosis, D-dimer, oxygen partial pressure, PAOI and left process of interventricular septum among four groups (H ≥ 12.350, P < 0.01). PAOI was moderately positively correlated with D-dimer (r = 0.443, P < 0.001) and left process of interventricular septum (r = 0.520, P < 0.001), and was weakly positively correlated with lower extremity venous thrombosis (r = 0.399, P < 0.001), left pulmonary artery diameter (r = 0.213, P = 0.014) and inferior vena cava regurgitation (r = 0.229, P = 0.008). Lower extremity venous thrombosis (OR = 7.708, P < 0.001) and left process of interventricular septum (OR = 3.641, P = 0.008) were independent risk factors for the onset of APE. The combination of the two indicators was effective for diagnosis of APE, and AUC was 0.795 (95% CI 0.715 to 0.874). ConclusionCTPA may be applied to evaluate the severity of APE and right heart function in rehabilitation patients.

Objective:To analyze the relevant situation of hospital patents, and to put forward suggestions to improve the efficiency of patent transformation.Methods:The Patsnap database was used to analyze the general trend, technical field distribution, application contribution, cooperative application, patent value, and achievement transformation of Peking University Cancer Hospital from 2012 to 2021, to provide a reference for the patent layout and achievement transformation of the hospital.Results:Through analysis, the number of hospital patent applications in recent years is obviously increasing, mainly for invention patents; the patent IPC classification is concentrated in A61, C12, C07, and other technical fields; the first inventors of the patents are concentrated; the cooperative patent applications were rare; the patent values are not high.Conclusions:The hospital should build an achievement promotion platform, establish a science and innovation community, set up an incubation fund, and innovate a transformation mode, to improve innovation-driven efficiency.