BACKGROUND:A large number of studies have confirmed that the therapeutic effectiveness of mesenchymal stem cell secretome is comparable to that of mesenchymal stem cells,but the mechanism of its action is still unclear. OBJECTIVE:To summarize the research progress of mesenchymal stem cell secretome in recent years,to investigate the molecular mechanism of its therapeutic effect,to analyze the current problems and to look forward to the future development. METHODS:The terms"exosomes,mesenchymal stem cells secrete,extracellular vesicles,mesenchymal stem cells,mechanism"were used as English search terms in the PubMed database.Articles that were not related to the research purpose of the article and duplicated articles were excluded.At the same time,we combined the method of literature tracking.Finally,109 articles that met the criteria were incuded for the review. RESULTS AND CONCLUSION:(1)The mesenchymal stem cell secretome promotes tissue repair and regeneration through delivering genetic material,immunomodulatory factors,growth factors,etc.to target cells,by activating anti-apoptotic,regulating angiogenesis,modulating fibrosis and pro-survival pathways in target cells.(2)The potential of mesenchymal stem cell secretome in disease therapy has also been confirmed.Numerous research results have shown that mesenchymal stem cell secretome can be used as a new cell-free treatment for inflammatory and degenerative diseases.(3)Mesenchymal stem cell secretome has been engineered to have more efficient therapeutic effects in recent years.However,due to the heterogeneity of the mesenchymal stem cell secretome and the complexity of its components,the exact mechanism of its therapeutic effect is still unclear.(4)At present,further research is needed to identify the key targets of mesenchymal stem cell secretome,and innovative specific and enhanced mesenchymal stem cell secretome should be developed by combining with engineering and genetic engineering technologies in the future.

OBJECTIVE To investigate the effects and potential mechanism of paeoniflorin on oxidative stress of ulcerative colitis （UC） mice based on adenosine monophosphate-activated protein kinase （AMPK）/nuclear factor-erythroid 2-related factor 2 （Nrf2） pathway. METHODS Male BALB/c mice were randomly divided into control group， model group， inhibitor group （AMPK inhibitor Compound C 20 mg/kg）， paeoniflorin low-， medium- and high-dose groups （paeoniflorin 12.5， 25， 50 mg/kg）， high- dose of paeoniflorin+inhibitor group （paeoniflorin 50 mg/kg+Compound C 20 mg/kg）， with 8 mice in each group. Except for the control group， mice in all other groups were given 4% dextran sulfate sodium solution for 5 days to establish the UC model. Subsequently， mice in each drug group were given the corresponding drug solution intragastrically or intraperitoneally， once a day， for 7 consecutive days. The changes in body weight of mice were recorded during the experiment. Twenty-four hours after the last administration， colon length， malondialdehyde （MDA） content， and activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） in colon tissues were measured； histopathological morphology of colon tissues， tight junctions between intestinal epithelial cells， and histopathological scoring were all observed and evaluated； the mRNA expressions of AMPK and Nrf2， as well as the protein expressions of heme oxygenase-1（HO-1）， occludin and claudin-1， were all determined in colon tissue. RESULTS Compared with model group， paeoniflorin groups exhibited recovery from pathological changes such as inflammatory cell infiltration and crypt damage in the colon tissue， as well as improved tight junction damage between intestinal epithelial cells. Additionally， significant increases or upregulations were observed in body weight， colon length， activities of SOD and GSH-Px， phosphorylation level of AMPK， and protein expression of Nrf2， HO-1， occludin， claudin-1， and mRNA expressions of AMPK and Nrf2； concurrently， MDA content and histopathological scores were significantly reduced （P＜ 0.05 or P＜0.01）. In contrast， the inhibitor group showed comparable （P＞0.05） or worse （P＜0.05 or P＜0.01） indicators compared to the model group. Conversely， the addition of AMPK inhibitor could significantly reverse the improvement of high- dose paconiflorin （P＜0.01）. CONCLUSIONS Paeoniflorin can repair intestinal epithelial cell damage in mice， improve tight junctions between epithelial cells， upregulate the expression of related proteins， and promote the expression and secretion of antioxidant-promoting molecules， thereby ameliorating UC； its mechanism may be associated with activating AMPK/Nrf2 antioxidant pathway.

Background: and Purpose This study aimed to investigate the association between residual inflammatory risk (RIR) and vulnerable plaques using high-resolution magnetic resonance imaging (HRMRI) in symptomatic intracranial atherosclerotic stenosis (ICAS). Methods: This retrospective study included 70%–99% symptomatic ICAS patients hospitalized from January 2016 to December 2022. Patients were classified into four groups based on high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein cholesterol (LDL-C): residual cholesterol inflammatory risk (RCIR, hs-CRP ≥3 mg/L and LDL-C ≥2.6 mmol/L), RIR (hs-CRP ≥3 mg/L and LDL-C <2.6 mmol/L), residual cholesterol risk (RCR, hs-CRP <3 mg/L and LDL-C ≥2.6 mmol/L), and no residual risk (NRR, hs-CRP <3 mg/L and LDL-C <2.6 mmol/L). Vulnerable plaque features on HRMRI included positive remodeling, diffuse distribution, intraplaque hemorrhage, and strong enhancement. Results: Among 336 included patients, 21, 60, 58, and 197 were assigned to the RCIR, RIR, RCR, and NRR groups, respectively. Patients with RCIR (adjusted odds ratio [aOR], 3.606; 95% confidence interval [CI], 1.346–9.662; P=0.011) and RIR (aOR, 3.361; 95% CI, 1.774–6.368, P<0.001) had higher risks of strong enhancement than those with NRR. Additionally, patients with RCIR (aOR, 2.965; 95% CI, 1.060–8.297; P=0.038) were more likely to have intraplaque hemorrhage compared with those with NRR. In the sensitivity analysis, RCR (aOR, 2.595; 95% CI, 1.201–5.608; P=0.015) exhibited an additional correlation with an increased risk of intraplaque hemorrhage. Conclusion In patients with symptomatic ICAS, RIR is associated with a higher risk of intraplaque hemorrhage and strong enhancement, indicating an increased vulnerability to atherosclerotic plaques.

Background: and Purpose This study aimed to investigate the association between residual inflammatory risk (RIR) and vulnerable plaques using high-resolution magnetic resonance imaging (HRMRI) in symptomatic intracranial atherosclerotic stenosis (ICAS). Methods: This retrospective study included 70%–99% symptomatic ICAS patients hospitalized from January 2016 to December 2022. Patients were classified into four groups based on high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein cholesterol (LDL-C): residual cholesterol inflammatory risk (RCIR, hs-CRP ≥3 mg/L and LDL-C ≥2.6 mmol/L), RIR (hs-CRP ≥3 mg/L and LDL-C <2.6 mmol/L), residual cholesterol risk (RCR, hs-CRP <3 mg/L and LDL-C ≥2.6 mmol/L), and no residual risk (NRR, hs-CRP <3 mg/L and LDL-C <2.6 mmol/L). Vulnerable plaque features on HRMRI included positive remodeling, diffuse distribution, intraplaque hemorrhage, and strong enhancement. Results: Among 336 included patients, 21, 60, 58, and 197 were assigned to the RCIR, RIR, RCR, and NRR groups, respectively. Patients with RCIR (adjusted odds ratio [aOR], 3.606; 95% confidence interval [CI], 1.346–9.662; P=0.011) and RIR (aOR, 3.361; 95% CI, 1.774–6.368, P<0.001) had higher risks of strong enhancement than those with NRR. Additionally, patients with RCIR (aOR, 2.965; 95% CI, 1.060–8.297; P=0.038) were more likely to have intraplaque hemorrhage compared with those with NRR. In the sensitivity analysis, RCR (aOR, 2.595; 95% CI, 1.201–5.608; P=0.015) exhibited an additional correlation with an increased risk of intraplaque hemorrhage. Conclusion In patients with symptomatic ICAS, RIR is associated with a higher risk of intraplaque hemorrhage and strong enhancement, indicating an increased vulnerability to atherosclerotic plaques.

Background: and Purpose This study aimed to investigate the association between residual inflammatory risk (RIR) and vulnerable plaques using high-resolution magnetic resonance imaging (HRMRI) in symptomatic intracranial atherosclerotic stenosis (ICAS). Methods: This retrospective study included 70%–99% symptomatic ICAS patients hospitalized from January 2016 to December 2022. Patients were classified into four groups based on high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein cholesterol (LDL-C): residual cholesterol inflammatory risk (RCIR, hs-CRP ≥3 mg/L and LDL-C ≥2.6 mmol/L), RIR (hs-CRP ≥3 mg/L and LDL-C <2.6 mmol/L), residual cholesterol risk (RCR, hs-CRP <3 mg/L and LDL-C ≥2.6 mmol/L), and no residual risk (NRR, hs-CRP <3 mg/L and LDL-C <2.6 mmol/L). Vulnerable plaque features on HRMRI included positive remodeling, diffuse distribution, intraplaque hemorrhage, and strong enhancement. Results: Among 336 included patients, 21, 60, 58, and 197 were assigned to the RCIR, RIR, RCR, and NRR groups, respectively. Patients with RCIR (adjusted odds ratio [aOR], 3.606; 95% confidence interval [CI], 1.346–9.662; P=0.011) and RIR (aOR, 3.361; 95% CI, 1.774–6.368, P<0.001) had higher risks of strong enhancement than those with NRR. Additionally, patients with RCIR (aOR, 2.965; 95% CI, 1.060–8.297; P=0.038) were more likely to have intraplaque hemorrhage compared with those with NRR. In the sensitivity analysis, RCR (aOR, 2.595; 95% CI, 1.201–5.608; P=0.015) exhibited an additional correlation with an increased risk of intraplaque hemorrhage. Conclusion In patients with symptomatic ICAS, RIR is associated with a higher risk of intraplaque hemorrhage and strong enhancement, indicating an increased vulnerability to atherosclerotic plaques.

Objective: To examine the association of 24 hour movement behaviors with emotional and behavioral problems among left behind children, so as to provide a theoretical reference for the practice of 24 hour activity interventions to promote emotional and behavioral problems in this population. Methods: From February to May 2023, 1 117 left behind children in grades 4-6 from 10 primary schools in five cities in Zhejiang Province were selected using a convenient cluster sampling method to conduct a questionnaire survey examining 24 hour movement behaviors, as well as emotional and behavioral problems. The general linear model was adopted to analyze the association between satisfying the 24 hour movement behavior guidelines, and emotional and behavioral problems among left behind children. Results: The sleep duration compliance rate was the highest (52.19%), while the moderate-to-vigorous PA (MVPA) compliance rate was the lowest (17.73%). The compliance rate of the three activities accounted for 7.43 %. There was a dose response between the number of guidelines satisfied, and the emotional and behavior of left behind children; that was, satisfaction of a higher number of guidelines was associated with a lower risk of emotional and behavioral problems among left behind children (difficulty factor: β=-0.56, 95%CI =-1.23--0.19; strength factor: β=0.50, 95%CI =-0.48-1.22, P < 0.01). Compared to satisfying none of the guidelines, satisfying the guidelines for screen time ( β=-0.23, 95%CI =-2.18- -0.14 ) and sleep duration ( β=-0.13, 95%CI =-1.66--0.11) was negatively correlated with the difficulty factor, while satisfying the guideline for MVPA ( β=0.13, 95%CI =0.09-1.08) and sleep duration ( β=0.18, 95%CI =0.09-1.40) was positively associated with the strength factor. In addition, satisfying two or all three of the guidelines was more strongly associated with these outcomes than satisfying one of the recommendations ( P <0.01). Conclusions Meeting the 24 hour movement behavior guidelines can improve emotional and behavioral problems among left behind children. It is necessary to raise their awareness of the effect of satisfying the 24 hour movement behavior guidelines and formulate comprehensive intervention measures.

In recent years， the incidence of pulmonary nodules has kept rising. To give full play to the advantages of traditional Chinese medicine （TCM） in the treatment of pulmonary nodules and identify the breakthrough points of integrating TCM with Western medicine， the China Association of Chinese Medicine organized medical experts in TCM and western medicine to carry out in-depth discussion regarding this disease. The discussion encompassed the modern medical advances， TCM theories of etiology and pathogenesis， the role and advantages of TCM in the whole course management of pulmonary nodules， contents and methods of research on pulmonary nodules， and science popularization work， aiming to provide a reference for clinical practice and scientific research. After discussion， the experts concluded that the occurrence of pulmonary nodules was rooted in the deficiency of the lung and spleen and triggered by phlegm dampness， blood stasis， and Qi stagnation. TCM can treat pulmonary nodules by controlling and reducing nodules， improving physical constitution， ameliorating multi-system nodular diseases， reducing anxiety and avoiding excessive diagnosis and treatment， and serving as an alternative for patients who are unwilling or unfit for surgical treatment. At present， the optimal diagnosis and treatment strategy for pulmonary nodules has not been formed， which needs to be further studied from multiple perspectives such as clinical epidemiology， biology， and evidence-based medicine. The primary task of current research is to find out the advantages， effective prescriptions， and target populations and determine the effective outcomes of TCM in the treatment of pulmonary nodules. At the same time， basic research should be carried out to explore the etiology and biological behaviors of pulmonary nodules. The expert consensus on the diagnosis and treatment of pulmonary nodules with integrated TCM and Western medicine needs to be continuously revised to guide clinicians to conduct standardized， scientific， and accurate effective diagnosis and treatment.

ObjectiveTo investigate the clinical efficacy of lumbar core muscle stability training combined with kinesiology taping technique in the rehabilitation treatment of lumbar disc herniation （LDH）. MethodsA total of 99 LDH patients treated in Ningbo Yinzhou No. 2 Hospital from January 2018 to January 2020 were selected and divided into control group （n=49） and observation group （n=50）. Kinesiology taping technique was applied to patients in the control group and patients in the observation group were treated with lumbar core muscle stability training combined with kinesiology taping technique， then we compared the therapeutic effect， lumbar function and pain degree， surface electromyography of lumbar extensor muscles， lumbar range of motion， LDH recurrence and skin allergies before and after the treatment between the two groups. ResultsAfter 4 weeks of treatment， compared with those in the control group， in the observation group， the visual analogue scale （VAS） and Oswestry disability index （ODI） scores were significantly lower （P<0.05）； the Japanese Orthopaedic Association （JOA） score， mean power frequency of lumbar extensor muscles， integral electromyography value and lumbar function score were significantly higher （P<0.05）. During the treatment， there was no significant difference in the incidence of complications between two groups （P>0.05）. After 4 weeks of treatment， the observation group had a significantly lower LDH recurrence rate than the control group （P<0.05）. ConclusionLumbar core muscle stability training combined with kinesiology taping technique achieves a significantly better therapeutic effect than kinesiology taping technique in the rehabilitation treatment of LDH and can effectively relieve muscle fatigue， help alleviate lumbar spine pain and improve the function of lumbar spine.

ObjectiveTo explore the protective mechanism of paeoniflorin on mice with ulcerative colitis （UC） through the adenosine monophosphate-activated protein kinase （AMPK）/mammalian target of rapamycin （mTOR） autophagy pathway. MethodUC mouse model was established by allowing mice freely drink 4% DSS， and 56 BALB/c male mice were randomly divided into model group， AMPK inhibitor group （20 mg·kg^-1）， paeoniflorin （50 mg·kg^-1） + inhibitor （20 mg·kg^-1） group， and high dose （50 mg·kg^-1）， medium dose （25 mg·kg^-1）， and low dose （12.5 mg·kg^-1） paeoniflorin groups. After seven days of drug intervention， the protective effect of paeoniflorin on mice with UC was determined by comparing the body weight， disease activity index （DAI） changes， and Hematoxylin-eosin （HE） staining results. Enzyme linked immunosorbent assay （ELISA） was used to detect the levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in the serum of mice in each group， and immunofluorescence was utilized to detect microtubule-associated protein 1 light chain 3 （LC3） content in the colon， AMPK， mTOR proteins， and their phosphorylated proteins including p-AMPK and p-mTOR in the colon tissue were detected by Western blot， and the mRNA expression levels of AMPK， mTOR， Beclin1， LC3， and p62 were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the blank group， the model group showed a decrease in body mass， an increase in DAI score， and severe pathological damage to the colon. The levels of inflammatory factors including TNF-α and IL-6 increased in serum （P<0.01）， while the protein levels of LC3 and p-AMPK/AMPK were down-regulated in colon tissue， and those of p-mTOR/mTOR were up-regulated （P<0.01）. The mRNA expression levels of AMPK and LC3 were down-regulated， while the mRNA expression levels of mTOR and p62 were up-regulated （P<0.01）. Compared with the model group and the paeoniflorin + inhibitor group， the mice treated with paeoniflorin showed an increase in body mass， a decrease in DAI score， a reduction in pathological damage to colon tissue， and a reduction in the levels of inflammatory factors of TNF-α and IL-6 in serum （P<0.05）. The protein levels of LC3 and p-AMPK/AMPK in colon tissue were up-regulated， while the protein levels of p-mTOR/mTOR were down-regulated （P<0.01）. The mRNA expression levels of AMPK， Beclin1， and LC3 were up-regulated， while the mRNA expression of mTOR and p62 were down-regulated （P<0.01）. The colon tissue of the inhibitor group was severely damaged， and the trend of various indicators was completely opposite to that of the high dose paeoniflorin group. ConclusionPaeoniflorin can enhance autophagy and reduce inflammatory damage in mice with UC by activating the AMPK/mTOR signaling pathway and thus play a protective role.

Objective:To prepare the anti-programmed death-ligand 1 (PD-L1) nanoantibody P3C8-C3Fab by ligating with C3Fab and to investigate its role in plasma half-life.Methods:The C3Fab peptide derived from protein G was molecularly fused with the nanobody P3C8 by DNA recombination technology. The nanoantibody P3C8-C3Fab was inducibly expressed and purified in the E. coli BL21 strain, and the binding of it to PD-L1 protein, mouse IgG, and PD-L1-expressing tumor cells was detected by enzyme-linked immunosorbent assay (ELISA). The residual P3C8-C3Fab was detected in mouse serum at different times using double-antibody sandwich ELISA to assess the prolongation of the plasma half-life of PD-L1 nanobodies by C3Fab. Results:The nanoantibody P3C8-C3Fab was successfully constructed, and it could efficiently express itself in soluble form in BL21. The purified NbP3C8-C3Fab protein was obtained with a mass fraction of about 90% at a yield of 7.18 mg/L. The affinity of P3C8-C3Fab for PD-L1 protein and mouse IgG gradually increased with increasing mass concentration and showed a concentration correlation. The binding of P3C8-C3Fab to lung cancer A549 cells showed a concentration correlation. The concentration standard curve of P3C8-C3Fab in mouse serum showed a typical S-shape with a concentration correlation. The plasma half-life of P3C8 was only 0.44 h, while the plasma half-life of P3C8-C3Fab was 21.27-fold higher, up to 9.36 h.Conclusions:The linkage of C3Fab to the nanobodies of P3C8 can significantly prolong the plasma half-life of P3C8, which is valuable for the improvement of in vivo nanobody effects.