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.

OBJECTIVE To investigate the neuroprotective effect and mechanism of eleutheroside B （ELB） on Parkinson’s disease （PD） model mice by regulating the IκB kinase β （IKKβ）/nuclear factor-κB （NF-κB） signaling pathway. METHODS Fifty mice were randomly divided into normal control group， model group， positive control group （selegiline hydrochloride， 10 mg/kg）， and ELB low-dose and high-dose groups （80， 160 mg/kg）， with 10 mice in each group. Each group was given relevant medicine or normal saline intragastrically for 14 consecutive days. Starting from the 10th day of administration， the model group and all administration groups were intraperitoneally injected with 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine （MPTP） 30 mg/kg， for five consecutive days to establish the chronic PD model. After the last administration for 24 h， six mice were randomly selected from each group to test their behavioral abilities； detect the levels of interleukin-1β （IL-1β）， IL-10， tumor necrosis factor-α （TNF-α） in brain tissue and their mRNA expressions were measured， and positive expression of tyrosine hydroxylase （TH）， protein expressions of TH， α -synuclein （ α -syn）， ionized calcium-binding adaptor molecule 1 （Iba-1）， as well as phosphorylation levels of IKKβ and NF-κB p65 proteins in the brain tissue were detected. The ultrastructure of neurons in substantia nigra was observed. RESULTS Compared with the model group， rotarod endurance time and climbing score of each administration group （except for the ELB low-dose group） were increased significantly （ P ＜0.05）， while the levels and mRNA expressions of IL-1β， TNF-α， α -syn， and Iba-1， as well as phosphorylation levels of IKKβ and NF-κB p65 proteins in brain tissue were decreased significantly （except for TNF-α in the ELB low-dose group）. Conversely， the level and mRNA expression of IL-10 （except for the ELB low-dose group）， TH positive expression and protein expressions were significantly increased （ P ＜0.05）. Typical neurodegenerative pathological changes， such as neuronal karyopyknosis， mitochondrial swelling and vacuolization， and endoplasmic reticulum dilation， all showed varying degrees of improvement. CONCLUSIONS ELB may exert neuroprotective effects by inhibiting the activation of the IKKβ/NF-κB signaling pathway， alleviating inflammatory responses， reducing abnormal α -syn aggregation and neuronal loss， and further improving motor dysfunction in PD mice.

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.

Background Air pollution has widespread adverse health effects on human health, but research on its impact on reproductive health and related physiological mechanisms remains insufficient. Objective To investigate the associations between short-term exposure to particulate matter and nitrogen dioxide (NO₂) and serum levels of anti-Müllerian hormone (AMH) and testosterone in healthy adults. Methods A total of 152 healthy adults were recruited for a panel study, undergoing four follow-up visits from September 2019 to January 2020. Basic demographic information and serum samples were collected. Reproductive hormone levels were measured by enzyme-linked immunosorbent assay kits. Concurrently, environmental data in the study area were monitored, including fine particulate matter (PM_2.5), black carbon (BC), NO₂, particle number concentrations in the 5-560 nm size fraction (PNC_{5_560}), and meteorological variables. Linear mixed-effects models were constructed to estimate the effects of short-term exposure to these particulate matter on serum reproductive hormone levels. Results The participants had an average age of (23.9±2.4) years, with 102 women. For each interquartile range (IQR) increment in pollutant moving average concentrations, PM_2.5, PNC_{5_25}, PNC_{100_560}, BC, and NO₂ were associated with relative decreases in female serum AMH levels by 10.2%-16.9%, 46.2%-58.0%, 16.9%-21.2%, 14.8%-26.5%, and 11.3%-17.6%, respectively. These negative associations were stronger in females with waist-to-hip ratio > 0.76 and physical activity levels ≤ 1217 metabolic equivalents (MET) min per week. Similarly, in males, an IQR increase in the same pollutants was associated with relative decreases in serum free testosterone by 11.1%-17.2%, 35.2%, 10.5%-18.9%, 18.7%-24.2%, and 10.3%-26.0%, respectively. These effects were more pronounce in male with a waist-to-hip ratios > 0.81 and physical activity levels ≤ 1498 MET-min per week. Conclusion Short-term exposure to particulate matter and NO₂ may reduce serum levels of AMH and testosterone in healthy adults. Furthermore, these adverse effects appears to be stronger in adults with higher waist-to-hip ratios.

Objective To analyze the relationship between serum forkhead box protein O1(FOXO1)and myeloid cell trigger receptor 2(TREM2)levels and brain edema volume and nerve function in patients with cerebral hemorrhage.Methods Clinical data of 150 patients with cerebral hemorrhage(test group)who received treatment in our hospital from January 2021 to January 2023 were retrospectively collected,and 60 healthy patients who came to our hospital for physical examination during the same period were selected as the control group.The levels of FOXO1 and TREM2 were compared between the two groups.Using the median FOXO1 and TREM2 as nodes,the patients were divided into high level and low level observation groups,and the differences of edema volume and National Institutes of Health Stroke Scale(NIHSS)scores were compared among different groups at admission,3 days after admission and 5 days after admission.Pearson analyzed the correlation of serum FOXO1 and TREM2 levels with edema volume and nerve function.Results The levels of FOXO1 and TREM2 in the observation group were(10.45±1.17)ng/ml and(23.96±1.57)ng/L,respectively,while those in the control group were(8.15±1.06)ng/L and(20.70±0.65)ng/L,respectively.There was a statistically significant difference between the two groups(P＜0.05).The brain edema volume and NIHSS score in patients with different FOXO1 level and TREM2 level were compared at F time point,F interaction,and F among groups(P＜0.05).The brain edema volume and NIHSS score showed a trend of change with time,and there were differences between groups.Higher FOXO1 and TREM2 level group had higher cerebral edema volume at admission,3 days after admission and 5 days after admission,and higher FOXO1 and TREM2 level group had higher scores at 3 days after admission and 5 days after admission(P＜0.05).The levels of FOXO1 and TREM2 were positively correlated with cerebral edema volume at admission,3 d and 5 d,and were positively correlated with 3 d and 5 d NIHSS scores at admission(P＜0.05).Conclusion Patients with cerebral hemorrhage have abnormal FOXO1 and TREM2 high expression,and FOXO1 and TREM2 levels are significantly positively correlated with brain edema volume and nerve function impairment.

Objective:To analyze the association between inflammation-related dietary patterns and the risk for cognitive impairment in older adults aged ≥65 years in longevity areas in China by using reduced rank regression (RRR) analysis.Methods:This study used cross-sectional data from the 2021 Healthy Aging and Biomarkers Cohort Study, including the information about study participants' demographic characteristics, lifestyles, daily life activities, and disease histories. Dietary intake was obtained by using a simplified food frequency questionnaire. Cognitive impairment was evaluated based on the Mini-Mental State Examination Scale combined with years of education. Fasting venous blood samples were collected to detect inflammatory markers, especially high-sensitivity C-reactive protein (hs-CRP) and the platelet-to-lymphocyte ratio (PLR). RRR analysis was used to obtain inflammation-related dietary patterns using hs-CRP and PLR as response variables. Multivariate logistic regression model was used to analyze the association between dietary pattern score and the risk for cognitive impairment. Restricted cubic spline was used to explore the dose response relationship, and mediation analysis was used to quantify the mediating effects of hs-CRP and PLR.Results:Two dietary patterns were identified with RRR. The primary pattern was characterized by higher intakes of flour, red meat, and dairy products, and lower intake of fresh vegetables, explaining 6.84% of the variance in food intake and 0.50% of the variance in inflammatory markers. Compared with the T1 group, the T3 group had significantly higher risk for cognitive impairment ( OR=1.242, 95% CI: 1.034-1.491). Each one standard deviation increase in the dietary pattern score was associated with an 8.7% increase in the risk for cognitive impairment ( OR=1.087, 95% CI: 1.008-1.172), with a significant linear trend (overall-model P<0.001, non-linear P=0.295). Mediation analysis indicated that hs-CRP mediated 6.2% of the association between the dietary pattern and the risk for cognitive impairment. Conclusion:The inflammation- related dietary pattern characterized by higher consumption of flour, red meat, and dairy products and lower consumption of fresh vegetables is associated with an increased risk for cognitive impairment in older adults, and hs-CRP partially mediates this association.

Objective:To explore the relationships between physical activity and cognitive impairment in older adults aged ≥65 years in longevity areas in China.Methods:A total of 6 081 older adults aged ≥65 years from the Healthy Ageing and Biomarkers Cohort Study in China in 2021 were included in this study. Information about their demographic characteristics, lifestyles, and chronic disease histories were collected, the intensity of physical activity was evaluated by using Physical Activity Scale for the Elderly, and the cognitive function was evaluated by using Mini-Mental State Examination Scale (Chinese version). Multifactorial logistic regression model was used to analyze the associations between different levels and types of physical activity and cognitive impairment in older adults.Results:In the 6 081 older adults, 1 829 (30.1%) had cognitive impairment. After adjusting for confounders, older adults with T2 and T3 levels of physical activity had lower risks for cognitive impairment compared with those with T1 levels of physical activity, with ORs of 0.47 (95% CI: 0.40-0.55) and 0.22 (95% CI: 0.18-0.28). The results of different types of physical activities showed that the ORs in leisure activity T2 and T3 groups were 0.52 (95% CI: 0.44-0.63) and 0.49 (95% CI: 0.41-0.58), and the ORs in housework activity T2 and T3 groups were 0.36 (95% CI: 0.30-0.42) and 0.19 (95% CI: 0.16-0.24). There was no significant association between work-related activity and cognitive impairment. Conclusion:There is a negative association between the intensity level of physical activity and cognitive impairment, and active leisure and household activities might reduce the risk for cognitive impairment.

Objective To explore the value of diffusion-weighted imaging(DWI)and apparent diffusion coefficient(ADC)in magnetic resonance imaging(MRI)in differential diagnosis of benign and malignant cervical lymph nodes in patients with nasopharyngeal carcinoma.Methods Clinical data of 98 patients diagnosed with nasopharyngeal carcinoma were retrospectively analyzed.This cohort included 65 patients with pathologically confirmed malignant lymph nodes and 33 patients with benign lymph nodes.Prior to pathological diagnosis,all patients underwent routine MRI scans and DWI.ADC values of both benign and malignant lymph nodes were recorded.The diagnostic performance was evaluated using receiver operating characteristic(ROC)curve analysis.Additionally,the diagnostic efficacy of MRI and ADC values in distinguishing benign and malignant lymph nodes of nasopharyngeal carcinoma was compared.Results Of the 65 patients with malignant lymph nodes,42 cases were accompanied by liquefactive necrosis,and 13 cases were accompanied by extracapsular invasion.Most benign lymph nodes showed no signal on DWI sequence,while malignant lymph nodes showed obvious high signal or mixed signals.The ADC value of benign lymph nodes was(1.724±0.365)×10-3 mm2/s,which was higher than that of malignant nodes(1.022±0.210)×10-3 mm2/s(P＜0.01).The ROC curve analysis results showed that the area under the curve of ADC value for diagnosing benign and malignant lymph nodes was 0.843(95%CI:0.782-0.904),with a cutoff value of 1.363×10-3 mm2/s.At this point,the sensitivity and specificity for differentiating benign and malignant lymph nodes were 0.856 and 0.849,respectively,and Youden index was 0.705.When the ADC value was lower than the cutoff value,the accuracy,sensitivity and specificity for differentiating cervical lymph nodes in nasopharyngeal carcinoma patients were 0.878,0.892 and 0.848,respectively,which were superior to MRI(P＜0.05).Conclusion The DWI images of malignant lymph nodes in patients with nasopharyngeal carcinoma show high signal and low ADC,and ADC has high efficiency in the differential diagnosis of benign and malignant cervical lymph nodes.

Objective:To explore the relationship between urinary cadmium levels and thyroid hormone levels in people aged 40-89 years old in selected areas of China.Methods:Based on the "Investigation of the Impact of Soil Quality of Agricultural Land on Human Health in Typical Areas" project from October 2019 to August 2020, a multi-stage stratified random sampling method was used to include 6 588 middle-aged and older adults aged 40-89. Demographic characteristics, dietary frequency and disease status were collected through the questionnaire and physical examination. Urinary cadmium and urinary creatinine were detected by random midstream urine. Fasting venous blood was collected for the detection of Triiodothyronine (T3) and Thyroxine (T4). The linear mixed effects model was used to explore the association of urine cadmium levels with thyroid hormone levels. Its dose-response relationship was explored by using the restricted cubic spline.Results:The age of the subjects was (63.48±12.18) years, with males accounting for 51.28%. The M ( Q 1,Q 3) of urinary cadmium level, T3 and T4 was 2.48 (1.36, 4.42) μg/g·creatinine, (1.96±0.51) nmol/L and (113.75±29.11) nmol/L, respectively. The linear mixed effects model showed that the changes of T3 and T4 were 0.027 (0.009, 0.044) nmol/L and 2.019 (1.084, 2.953) nmol/L for each one-unit increase (natural logarithm transformed) of urinary cadmium. The restricted cubic spline showed that there was a positive nonlinear association between urinary cadmium and T3 as well as T4 (all Pnonlinear<0.05). Conclusion:In selected areas of China, the urinary cadmium level of middle-aged and older adults aged 40-89 years is positively associated with T3 and T4.