BACKGROUND:A large number of studies have demonstrated that stem cell exosomes play an important role in the repair of bone defects,either directly as carriers for loading other small molecules or surface modifications,or by binding to biomaterials to promote the repair and regeneration of bone tissue.OBJECTIVE:To summarize the osteogenic mechanisms of stem cell exosomes from different sources and their research progress in bone defect repair.METHODS:Chinese search terms"stem cell,exosome,bone,biomaterial,carrier,bioceramic,polymer,metal,hydrogel,engineered exosome"were used to search CNKI.English search terms"stem cell,exosome,bone defect,biomaterial,carrier,bioceramic,ploymer,metal material,hydrogel,engineering exosome"were used to search PubMed database.According to the inclusion and exclusion criteria,77 relevant articles were finally included for summary.RESULTS AND CONCLUSION:Exosomes from stem cells of different origins can promote osteoblast proliferation and differentiation,promote angiogenesis,and regulate osteoclast activity and macrophage phenotype to promote bone formation and bone mineralization.In addition,many achievements of exosomes in the field of bone defect repair were described from two aspects:biomaterial-assisted exosomes and engineered exosomes.However,the current research on stem cell exosomes in bone tissue engineering is still insufficient,and most of these studies are limited to small animal models,while the treatment of bone defects in large animals,including humans,will be more complex,which will also become a major challenge for the treatment of bone defects.This will also be a great challenge in the dissemination of exosome therapy.

BACKGROUND:A large number of studies have demonstrated that stem cell exosomes play an important role in the repair of bone defects,either directly as carriers for loading other small molecules or surface modifications,or by binding to biomaterials to promote the repair and regeneration of bone tissue.OBJECTIVE:To summarize the osteogenic mechanisms of stem cell exosomes from different sources and their research progress in bone defect repair.METHODS:Chinese search terms"stem cell,exosome,bone,biomaterial,carrier,bioceramic,polymer,metal,hydrogel,engineered exosome"were used to search CNKI.English search terms"stem cell,exosome,bone defect,biomaterial,carrier,bioceramic,ploymer,metal material,hydrogel,engineering exosome"were used to search PubMed database.According to the inclusion and exclusion criteria,77 relevant articles were finally included for summary.RESULTS AND CONCLUSION:Exosomes from stem cells of different origins can promote osteoblast proliferation and differentiation,promote angiogenesis,and regulate osteoclast activity and macrophage phenotype to promote bone formation and bone mineralization.In addition,many achievements of exosomes in the field of bone defect repair were described from two aspects:biomaterial-assisted exosomes and engineered exosomes.However,the current research on stem cell exosomes in bone tissue engineering is still insufficient,and most of these studies are limited to small animal models,while the treatment of bone defects in large animals,including humans,will be more complex,which will also become a major challenge for the treatment of bone defects.This will also be a great challenge in the dissemination of exosome therapy.

Purpose: Dual anti–human epidermal growth factor receptor 2 (HER2) drugs have become the standard regimen for neoadjuvant systemic treatment (NST) to HER2-positive breast cancer patients. However, the efficacy varies greatly among patients with different HER2 protein expression levels. Materials and Methods: A total of 575 HER2-positive breast cancer patients from multiple centers throughout China from 2013 to 2022 were retrospectively analyzed. We compared clinicopathological features in different HER2 immunohistochemistry classes (HER2 2+/in situ hybridization [ISH] + or HER2 3+), and their difference in response to NST and survival with single or dual anti-HER2 drugs. Drug sensitivity assays were used to evaluate different efficacy of anti-HER2 drugs in vitro. Results: Compared to HER2 3+ subgroup, the HER2 2+/ISH+ group had a higher proportion of hormone receptor–positive status (48.7% vs. 76.1%, p < 0.001), more HER2 protein loss after NST, lower pathological complete response (pCR) rate (46.07% vs. 16.24%, p < 0.001), and tended to have worse disease-free survival (DFS). In HER2 2+/ISH+ patients, treated with pertuzumab and trastuzumab in combination had no significant improvement in pCR (19.12% vs. 12.24%, p=0.287) and DFS (p=0.908) than using alone. Drug sensitivity assay showed poor efficacy with dual anti-HER2 drugs in HER2 2+/ISH+ cell lines; however, fam-trastuzumab deruxtecan drugs had a satisfactory effect. Conclusion Owing to the differences in clinicopathological features and treatment efficacy, we considered the HER2 2+/ISH+ group to be a distinct subtype and defined it as the HER2-moderate–positive subgroup. In this subgroup, dual anti-HER2 drugs did not exert significant improvement in pCR and DFS. Therefore, treatment optimization is warranted, with antibody-drug conjugate drugs as potential options.

BackgroundThe prevalence， disability rate and mortality rate of cerebral small vessel disease （CSVD） are relatively high among the elderly population， imposing a heavy burden on families and society. Among the various clinical manifestations of CSVD， cognitive impairment is the most common， and it is also the most closely related neuro-psychiatric syndrome to clinical practice in psychiatry. Previous studies on CSVD-related cognitive impairment （CSVD-CI） have mostly focused on the field of imaging， while studies on non-invasive electrophysiological and cerebral hemodynamic assessments are relatively scarce. ObjectiveTo analyze the characteristics of event-related potential （ERP） and functional near-infrared spectroscopy （fNIRS） in patients with CSVD-CI， and to explore their correlations with the severity of white matter lesions， in order to provide references for the objective assessment and early identification of CSVD-CI. MethodsA total of 40 patients with CSVD who met the diagnostic criteria of the Chinese Guideline for Diagnosis and Treatment of Cerebral Small Vessel Disease （2020） and had cognitive impairment， as well as were admitted to the Affiliated Hospital of North Sichuan Medical College from December 2024 to December 2025， were enrolled as the case group. Meanwhile， 40 healthy volunteers matched for gender， age and education level were recruited as the control group. Both groups underwent assessment using the Mini-Mental State Examination （MMSE）， ERP-P300 detection， and fNIRS examination. The ERP-P300 indicators， functional connectivity strength of the whole brain and cognitive-related regions of interest （ROI） in fNIRS of the two groups were compared. The severity of the patients' white matter lesions was classified as follows： the Fazekas grade I group （mild white matter lesions） and the Fazekas grades II to III group （moderate to severe white matter lesions）. Spearman correlation analysis was employed to investigate the correlation between the Fazekas grading of brain white matter lesions and the latency of ERP-P300， as well as the strength of functional connectivity measured by fNIRS. ResultsThe MMSE score of the CSVD-CI group was lower than that of the control group （Z=-6.250， P<0.01）， and ERP-P300 lantency was significantly longer than that of the control group （t=12.291， P<0.01）. The MMSE score of the sub-group with Fazekas grade I was higher than that of the sub-groups with grades II to III （Z=-2.420， P<0.05）， and showed a shorter P300 latency than that of the sub-groups with grades II to III （Z=-4.210， P<0.01）. All the differences were statistically significant. The resting-state whole-brain functional connectivity strength in the CSVD-CI group was lower than that in the control group， and the difference was statistically significant （t=10.243， P<0.05）. Compared with the control group， the differences in the functional connectivity strength within the left premotor cortex （PMC）， right PMC， left frontopolar cortex （FPC）， right FPC， left dorsolateral prefrontal cortex （DLPFC）， right DLPFC， left orbitofrontal cortex （OFC）， and right OFC regions in the CSVD-CI group were all statistically significant （P_{FDR correction}<0.01）. The differences in the functional connectivity strength between multiple prefrontal-related brain regions between the CSVD-CI group and the control group were all statistically significant （P_{FDR correction}<0.01）. The severity of white matter lesions in CSVD-CI patients was positively correlated with the P300 latency （r_s=0.891， P<0.05）， and negatively correlated with the fNIRS functional connectivity strength （r_s=-0.359， P<0.05）. ConclusionPatients with CSVD-CI exhibit prolonged P300 latency， as well as decreased functional connectivity strength in multiple brain regions including the whole brain and the prefrontal lobe during the resting state. Moreover， these indicators are correlated with the severity of white matter lesions.

Objective To understand the epidemiological characteristics and trends of postoperative pneumonia(POP)in tertiary general hospitals in Jiangsu Province,and provide theoretical basis for carrying out targeted pre-vention and control measures.Methods Surgery patients from 22 tertiary general hospitals in 12 cities in north,central,and south of Jiangsu Province from January 1,2022 to December 31,2023 were chosen as studied subjects,occurrence of POP was analyzed and compared.Results A total of 848 274 surgical procedures were performed in 22 hospitals,and 3 606 cases of POP occurred,with an incidence of 0.43％.The incidence in 2023 was 0.37％,which was lower than that in 2022(0.49％),with statistically significant difference(P＜0.001).The top three de-partments with high incidence of POP were neurosurgery(6.71％),cardiothoracic surgery(2.91％),and general surgery(0.77％).Among hospitals of different grades,the incidence of POP in tertiary first-class hospitals was 0.44％,which was higher than that in other tertiary hospitals(0.37％).There was no statistically significant difference in the incidence of POP between municipal and district/county hospitals(P＞0.05).The incidence of POP in hospitals with a bed:infection control full-time staff ratio＜200∶1 was lower than that in hospitals with the ratio ≥200∶1(0.39％vs 0.47％,P＜0.001),while the incidence of POP in hospitals with a proportion ≥30％of full-time staff being doctors was higher than that in hospitals with a proportion＜30％(0.45％vs 0.36％,P＜0.001).The incidence of POP in male patients was higher than that in female patients(0.62％vs 0.26％,P＜0.001).The incidence of POP in elderly patients aged≥65 was higher than that in patients aged＜65(0.73％vs 0.26％,P＜0.001).A total of 2 667 strains of infectious pathogens were detected,with the top three being Acine-tobacter baumannii,Klebsiella pneumoniae,and Pseudomonas aeruginosa,accounting for 28.95％,22.72％,and 15.45％,respectively.The detection rates of carbapenem-resistant Acinetobacter baumannii(CRAB),carba-penem-resistant Klebsiella pneumoniae(CRKP),and carbapenem-resistant Pseudomonas aeruginosa(CRPA)were 60.75％,21.45％,and 32.28％,respectively.The detection rate of CRKP decreased in 2023 compared with 2022,with statistically significant difference(P＜0.05).Conclusion The overall incidence of POP in tertiary general hos-pitals in Jiangsu Province is relatively low,but there are significant differences among different hospitals.There-fore,perioperative prevention and control measures should be carried out based on the epidemiological characteristics of patients.

Objective:To analyze the iodine nutrition status of children and adolescents and influencing factors in Zhejiang Province, providing scientific basis for optimizing iodine deficiency disorders (IDD) prevention and control strategies.Methods:In June 2022, a multistage stratified sampling method was used to divide 16 counties (cities, districts, abbreviated as counties) in Zhejiang Province into three categories based on their geographical locations (average distance from the coastline): coastal areas (including Dinghai District, Jiaojiang District, Sanmen County, Cixi City and Lucheng District), sub-coastal areas (including Wuxing District, Haining City, Linping District, Fuyang District and Fenghua District), and inland areas(including Suichang County, Changshan County, Shengzhou City, Jindong District, Dongyang City and Yongjia County). One county was selected from each category, and one township (street) was selected from each county. Two administrative villages (neighborhood committees) were selected from each township (street). Ten households including all children and adolescents aged 6-17 in each household were selected from each administrative village (neighborhood committee). Demographic information and personal dietary characteristics were collected via questionnaires, while household salt and a random urine sample were tested for iodine level. Trend analysis was conducted using a χ 2trend test, and a multivariate logistic stepwise regression model was used to analyze the influencing factors of urinary iodine levels. Results:A total of 755 children and adolescents aged 6-17 were selected, including 387 males (51.26%) and 368 females (48.74%), with an age of (11.24 ± 3.32) years. There were 269 children and adolescents in coastal areas (35.63%) and 409 children and adolescents in urban areas (54.17%). A total of 755 household salt samples were collected, with a median salt iodine concentration of 21.80 mg/kg. These included 263 non-iodized salt samples, 38 unqualified iodized salt samples, and 454 qualified iodized salt samples. The coverage rate of iodized salt was 65.17% (492/755), and the consumption rate of qualified iodized salt was 60.13% (454/755). The distribution of salt iodine quality among children and adolescents in different geographical locations showed statistically significant differences (χ 2 = 111.95, P < 0.001), with the proportion of non-iodized salt gradually decreasing from coastal areas to inland areas (χ 2trend = 90.17, P < 0.001). A total of 755 urine samples were collected, with a median urinary iodine concentration of 186.60 μg/L. The proportions of urinary iodine < 100, 100-199, 200-299, and ≥300 μg/L were 16.95% (128/755), 37.62% (284/755), 24.37% (184/755), and 21.06% (159/755), respectively. The χ 2trend test revealed a nonlinear positive correlation between salt iodine level and urinary iodine level (χ 2regression = 21.98, P < 0.001; χ 2partial = 6.96, P < 0.001). The frequency distribution of urinary iodine in children and adolescents from different geographical locations and between urban and rural areas showed statistically significant differences (χ 2 = 29.63, 16.56, P < 0.001). Among them, the proportion of children and adolescents with urinary iodine < 100 μg/L gradually decreasing from coastal areas to inland areas (χ 2trend = 6.15, P = 0.013). The results of multivariate logistic regression analysis revealed that sub-coastal regions, inland regions, and urban-rural regions ( OR = 1.57, 1.53, 1.64, 95% CI: 1.11-2.24, 1.03-2.27, 1.17-2.32, P < 0.05) were significantly associated with urinary iodine levels in children and adolescents aged 6-17. Conclusions:In 2022, the iodine nutrition of children and adolescents in Zhejiang Province is generally suitable, but there is a risk of iodine deficiency among coastal children and adolescents. Geographic location and urban/rural areas are influencing factors on iodine nutrition status of children and adolescents in Zhejiang Province.

Objective:To investigate the iodine nutrition status of children and pregnant women in different water iodine areas of Shandong Province.Methods:From February to September 2023, Leling City (iodine deficient), Gaotang County (moderate iodine), and Liangshan County (high iodine) in different water iodine areas of Shandong Province were selected as survey sites. One village was selected from each county (city) in five directions: east, west, south, north, and center. Forty children aged 8 to 10 years (balanced in age, half male and half female) and 20 pregnant women were selected as survey subjects in each village. Random urine samples of children and pregnant women were collected to test for urinary iodine. Meanwhile, thyroid examinations were conducted on children to calculate the goiter rate.Results:A total of 600 urine samples of children were tested, with a median urinary iodine level of 246.0 μg/L. The median urinary iodine levels of children in iodine deficient, moderate iodine and high iodine areas were 219.6, 208.0 and 446.0 μg/L, respectively ( n = 200, 200, 200). The median urinary iodine level of children in high iodine area was significantly higher than that in iodine deficient and moderate iodine areas ( P < 0.05). A total of 600 children underwent thyroid examinations, with a goiter rate of 5.8% (35/600). The goiter rate of children in iodine deficient, moderate iodine, and high iodine areas were 4.0% (8/200), 1.0% (2/200), and 12.5% (25/200), respectively. The goiter rate of children in high iodine area was significantly higher than that in iodine deficient and moderate iodine areas ( P < 0.05). A total of 247 urine samples of pregnant women were tested, with a median urinary iodine level of 158.2 μg/L. The median urinary iodine levels of pregnant women in iodine deficient, moderate iodine, and high iodine areas were 75.3, 175.2 and 321.2 μg/L, respectively ( n = 98, 84, 65). The median urinary iodine level of pregnant women in high iodine area was significantly higher than that in iodine deficient and moderate iodine areas, and the median urinary iodine level of pregnant women in moderate iodine area was significantly higher than that in iodine deficient area ( P < 0.05). Conclusion:The urinary iodine levels of children and pregnant women and the goiter rate of children in high iodine area of Shandong Province are significantly increased, and water iodine may be a key factor affecting the iodine nutrition status of the population.

Low rectal cancer accounts for a high proportion of colorectal cancer cases in China, and the choice of treatment strategies critically impacts patient prognosis and quality of life. With the advancement of precision treatment, clinical decision-making requires integrating multi-dimensional factors to move beyond the traditional "one-size-fits-all" approach. The authors focus on the anatomical complexity, high recurrence risk, and functional preservation demands of low rectal cancer, incorporating the latest research advances to explore precision treatment pathways in terms of preoperative high-resolution magnetic resonance imaging assessment, breakthroughs in immunotherapy and precision surgical techniques. Future efforts should further optimize individua-lized strategies through multimodal assessment and multidisciplinary collaboration, refining inte-grated approaches based on evidence-based medicine to enhance clinical efficacy and patient survival outcomes.

Objective:To evaluate the efficacy of gadolinium ethoxybenzyl- diethy-lenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced MRI features in the preoperative prediction of tertiary lymphoid structures (TLS) within hepatocellular carcinoma (HCC) lesions.Methods:This retrospective cross-sectional study included clinical and pathological data from 297 HCC patients treated at the Southwest Hospital, Army Medical University between June 2021 and November 2022. Based on postoperative pathology, patients were categorized into TLS-negative ( n=93) and TLS-positive ( n=204) groups. MRI features of HCC lesions using Gd-EOB-DTPA enhancement and relevant clinical data were analyzed. Intergroup comparisons of imaging features and laboratory findings were performed using independent sample t-test, Mann-Whitney U test, χ2 test, or Fisher exact test, as appropriate. The logistic regression analysis was conducted to identify independent predictors of TLS positivity. A predictive model was constructed and visualized using a nomogram. The model′s predictive performance and clinical utility were assessed using the receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). The area under the ROC curve (AUC) was compared using the DeLong test. Results:Significant differences were observed between the TLS-negative and TLS-positive groups in alpha-fetoprotein (AFP) levels, intratumoral hemorrhage, and peritumoral satellite nodules in the hepatobiliary phase ( P<0.05). Multivariate logistic regression identified intratumoral hemorrhage ( OR=0.123, 95% CI 0.070-0.216, P<0.001) and peritumoral satellite nodules in the hepatobiliary phase ( OR=0.236, 95% CI 0.093-0.596, P=0.002) as independent predictive factors for TLS-positivity. The imaging model based on these two features yielded an AUC of 0.764 (95% CI 0.709-0.809) for predicting TLS-positivity. When combined with AFP levels, the resulting clinical-imaging model achieved a superior AUC of 0.784 (95% CI 0.732-0.829), which was significantly higher than that of the imaging model alone ( Z=2.20, P=0.028). A nomogram was constructed based on the clinical-imaging model. The calibration curve demonstrated good predictive performance of the nomogram, and the DCA showed that the curve remained above the default line across a range of reasonable threshold probabilities, indicating that patients could derive clinical benefit. Conclusion:A nomogram model based on Gd-EOB-DTPA enhanced MRI features combined with AFP levels can effectively predict the presence of TLS in HCC.

Purpose To explore factors influencing vaginal delivery during the first stage of labor using intrapartum ultrasound and to construct predictive models for delivery decision-making.Materials and Methods A total of 473 nulliparous women admitted to Heping Hospital,Northern Theater General Hospital from July to December 2021 were prospectively enrolled as the training set.Clinical data on admission and fetal biometric parameters(biparietal diameter,femur length,head circumference and abdominal circumference)measured within one week before delivery were collected.Ultrasound assessments of fetal position,angle of progression(AOP)and head-perineum distance(HPD)were performed during the first stage of labor.The latent phase group(n=255)was subdivided into vaginal delivery group(n=186)and cesarean section group(n=69);the active phase group(n=218)was divided into vaginal delivery group(n=168)and cesarean section group(n=50).The associations between fetal position,AOP,HPD and vaginal delivery were analyzed,and predictive models were constructed for the latent phase(model 1)and active phase(model 2).A validation set of 547 women from January to September 2022 was used to evaluate model performance via area under the curve(AUC),calibration curves and decision curve analysis.Results In the latent phase,multivariate regression identified maternal height(OR=3.970,P=0.002),pre-pregnancy body mass index(OR=0.893,P=0.036),labor onset type(OR=2.415,P=0.045),neonatal birth weight(OR=3.728,P=0.002),AOP(OR=11.649,P<0.001)and HPD(OR=4.240,P=0.004)as significant predictors.The training and validation sets showed AUCs of 0.917 and 0.869,respectively.Goodness-of-fit tests indicated excellent model calibration(χ2=3.437,P=0.904;χ2=10.877,P=0.209).Decision curve analysis demonstrated strong clinical utility.For the active phase,significant predictors included maternal height(OR=6.532,P<0.001),neonatal birth weight(OR=11.890,P<0.001),fetal position(OR=4.600,P=0.003),AOP(OR=7.229,P<0.001)and HPD(OR=4.722,P=0.005).AUCs were 0.943(training)and 0.906(validation),with good calibration(χ2=4.340,P=0.740;χ2=9.836,P=0.277)and clinical applicability.Conclusion First stage ultrasound assessment of fetal position,AOP and HPD correlates with delivery outcomes.The developed nomogram models combining these parameters with clinical factors provide valuable guidance for delivery decision-making.