Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca²⁺, K⁺, and Na⁺, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca²⁺ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca²⁺ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca²⁺ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.

ObjectiveTo investigate the therapeutic effects and mechanism of decoctions from four kinds of processed products of Aconiti Radix Lateralis Praeparata（ARLP） in deficiency-cold syndrome. MethodsA total of 36 SD rats were randomly divided into the control group， model group， Shengfupian（SFP） group， Paofuzi（PFZ） group， Heishunpian（HSP） group and Paofupian（PFP） group with 6 rats in each group. Except for the control group， rats in other groups were administered hydrocortisone sodium succinate via intramuscular injection to induce a cold deficiency syndrome model. After 14 consecutive days， each ARLP decoction pieces was administered via continuous gastric lavage at a dose of 12 g·kg^-1·d^-1 for 7 d， while the control and model groups received an equivalent volume of physiological saline. After the end of administration， body weight， spleen weight and thymus weight were measured for calculating the spleen and thymus indexes. Hematoxylin-eosin（HE） staining was used to observe the pathological morphology of adrenal tissue. The fully automatic biochemistry analyzer was used to measure the total cholesterol（TC）， triglyceride（TG）， lactic dehydrogenase（LDH） and lactate（LAC） levels in serum. Enzyme-linked immunosorbent assay（ELISA） was employed to measure the contents of 17-hydroxycorticosteroid（17-OHCS）， cortisol（CORT）， triiodothyronine（T₃）， thyroxine（T₄）， thyrotropin（TSH）， immunoglobulin（Ig） M， IgG， cyclic adenosine monophosphate（cAMP） and cyclic guanosine monophosphate（cGMP）. Western blot was used to measure the protein expression levels of protein kinase A（PKA）， cAMP response element-binding protein（CREB）， silent information regulator 1（Sirt1） and peroxisome proliferator-activated receptor γ coactivator-1α（PGC-1α）. And high performance liquid chromatography（HPLC） was used to determine the content of major alkaloids， followed by Pearson correlation analysis with pharmacodynamic indicators. ResultsAfter modeling， compare with the control group， the model rats exhibited symptoms such as lethargy and loose stools， mild abnormalities were observed in adrenal tissue structure， and both spleen and thymus indices were significantly reduced（P<0.01）. Thyroid， adrenal and immune system functions were suppressed， with decreased serum cAMP level and significantly elevated cGMP level（P<0.01）. Compared with the model group， the adrenal injury by hydrocortisone sodium succinate were repaired and the spleen index were increased significantly in all four ARLP groups（P<0.05， P<0.01）. The thymus index in SFP and PFZ groups were increased significantly（P<0.05）. The contents of T₃， TSH， 17-OHCS and CORT were increased significantly in SFP and PFZ groups（P<0.05）. In addition， the content of IgG in SFP， PFZ and PFP groups were increased significantly（P<0.01）， while the content of IgM in PFZ and HSP groups were also increased significantly（P<0.05）. Regarding the cyclic nucleotide system， PFZ significantly elevated cAMP level while reducing cGMP level（P<0.05）， exhibiting the most pronounced effect among the four decoction pieces. For energy metabolism indicators， PFZ significantly improved abnormal markers including TC， TG， LDH， and LAC（P<0.05）. HSP showed marked improvement effects on TG， LDH， and LAC（P<0.05）. Both PFZ and SFP significantly elevated the expression levels of PKA， CREB， Sirt1， and PGC-1α proteins（P<0.01）. Additionally， the diester alkaloids in ARLP showed a strong positive correlation with TG， IgG， and CORT， a strong negative correlation with LAC， a moderate positive correlation with T₄， and moderate negative correlations with cAMP and spleen index. Monomeric alkaloids showed strong positive correlations with TG and IgG， strong negative correlations with LAC， moderate positive correlations with CORT and T₄， and moderate negative correlations with cAMP and spleen index. However， the content of water-soluble alkaloids showed strong positive correlations with TC， LDH， 17-OHCS， T₃， TSH， and thymus index， moderate positive correlations with cAMP， CORT， T₄， and spleen index， and moderate negative correlation with cGMP. ConclusionAmong different processed ARLP decoction pieces， PFZ processed according to ZHANG Zhongjing's method exhibits the most potent warming and cold-dispelling effects. Its pharmacological actions are mediated through regulating the thyroid， adrenal， immune， cyclic nucleotide systems， and material-energy metabolism pathways. Among these， water-soluble alkaloids show strong or moderate correlations with more indicators of deficiency-cold syndrome and exhibit the highest content in PFZ. Therefore， PFZ processed according to ZHANG Zhongjing's method may exert its warming and cold-dispelling effects through water-soluble alkaloids.

Although global brain science research has progressed rapidly in recent decades, several fundamental questions in neuroscience remain unresolved. In particular, the physical mechanism underlying neural signal transmission remains controversial, and the carriers responsible for neural information storage and retrieval have not yet been fully clarified. These unresolved issues motivate us to re-examine the processes of neural information generation, transmission, integration, storage, and retrieval from multiple perspectives. A key observation is that neural electromagnetic activities are closely associated with time. Their duration, temporal structure, and dynamic evolution play crucial roles in neural information processing. In this work, we analyze neural electromagnetic activities from the perspective of temporal scales (referred to here as the “time course”). By reviewing and integrating findings from previous studies, we examine the characteristic time requirements and dynamic features of neural processes occurring at different stages of information processing. These stages include neural signal generation, signal transmission along axons, synaptic integration, synaptic plasticity, and memory formation and retrieval. Based on this temporal analysis, we outline a framework describing neural electromagnetic activities across a wide range of time scales, spanning from microseconds to minutes, hours, or even longer periods associated with long-term memory, which suggests that neural information processing involves multiple physical processes operating at different time levels. Rapid electromagnetic events may occur on microsecond scales, whereas electrophysiological phenomena such as action potentials typically last on the order of milliseconds. Longer time scales are associated with synaptic plasticity and memory-related processes. From this perspective, we propose that the physical carrier of neural information may be transient electromagnetic pulses with durations on the microsecond scale. In this framework, action potentials can be interpreted as the macroscopic electrophysiological manifestation of underlying electromagnetic processes triggered by ionic currents across neuronal membranes. Rather than being the fundamental neural signal itself, the action potential may represent a measurable membrane-level response associated with the successful activation of these electromagnetic events. Moreover, we discuss a possible mechanism for long-term memory storage. Considering the apparent temporal contradiction between the millisecond-scale excitation of neurons and the long-term persistence of memories, we believe that long-term memory information may be stored within neural network topologies formed by electrical synapse coupling. Such structures, referred to as electrically coupled memory networks (ECMNs), may enable neurons within the same network to respond rapidly and synchronously to stimuli, thereby facilitating efficient memory retrieval. Overall, this study emphasizes the importance of considering the temporal organization of neural electromagnetic activities when interpreting neural signaling mechanisms. It may provide new insights into the physical nature of neural information carriers and the mechanisms of memory storage and retrieval. Furthermore, highlighting the potential role of electromagnetic interactions in neural activity may contribute to the development of new theoretical frameworks and experimental approaches in neuroscience. Such perspectives may also offer valuable references for future research on neural coding, brain function mechanisms, and neuromodulation technologies.

Hyperthermic intrathoracic chemotherapy (HITHOC) is a localized treatment that combines hyperthermia with medications such as chemotherapy, anti-angiogenic agents, targeted therapy, or immunotherapeutic agents. It has advanced clinical progress for conditions such as malignant pleural mesothelioma, pleural metastasis of lung cancer, and pleural dissemination of thymic tumors. Systematic analyses indicate that as an adjuvant therapy to cytoreductive surgery, HITHOC improves patient survival and effectively controls pleural effusion and pleural metastasis. It exerts antitumor effects by enhancing drug penetration through thermal effects, inducing apoptosis, and modulating the immune microenvironment. HITHOC combined with systemic therapies (e.g., chemotherapy, targeted therapy, and immunotherapy) demonstrates synergistic potential, but its role as a local treatment should be clearly defined as adjunctive within the comprehensive management of advanced-stage patients. Further research is needed to clarify its indications, standardized protocols, and long-term efficacy and to explore optimized regimens and personalized combination treatment strategies. This review delves into the key bottlenecks hindering the development of hyperthermia therapy, such as the lack of high-level evidence-based medicine and the absence of standardized diagnostic and efficacy evaluation criteria, and proposes potential solutions.

ObjectiveTo analyze the output and efficiency of chronic disease management services for hypertension and diabetes in community health service institutions in Shanghai, to evaluate the allocation and efficiency of chronic disease management resources, and to provide references for improving the efficiency of chronic disease management in Shanghai’s communities. MethodsA total of 73 community health institutions from 15 districts of Shanghai were selected. Based on the chronic disease management resource data of community health institutions in 2019, 2021, and 2023, descriptive methods and the BCC model in Data Envelopment Analysis (DEA) were used to analyze the resource allocation, service output, and the efficiency of chronic disease management services in community health institutions in Shanghai. ResultsFrom 2019 to 2023, the indicators of resource allocation and service output of community health service institutions in Shanghai all showed upward trends. In terms of service efficiency, the average number of chronic disease patients managed by each health technician decreased from 237 to 231, and the number of patients served per 1 000 working hours decreased from 54 to 44. DEA efficiency analyses showed that the average overall efficiency increased from 0.867 in 2019 to 0.886 in 2021 and then decreased to 0.811 in 2023. The average technical efficiency decreased from 0.901 to 0.847, which was the main reason for the decline in overall efficiency. The average scale efficiency showed an initial increase followed by a decrease, rising from 0.961 in 2019 to 0.977 in 2021 and dropping back to 0.955 in 2023. The number of strong effective districts (overall efficiency=1.000) decreased from 6 in 2019 to 3 in 2023, and the efficiency differences between districts expanded. The range of overall efficiency widened from 0.622‒1.000 to 0.513‒1.000, indicating a decline in overall efficiency and an increase in inter-district heterogeneity. ConclusionFrom 2019 to 2023, the total volume of resource allocation and service output for chronic disease management in community health service institutions in Shanghai increased continuously. However, both the service output efficiency and the overall resource allocation efficiency declined, driven primarily by a decrease in technical efficiency, and accompanied by widening inter‑district disparities.

Objective To analyze the pollution characteristics of PM_2.5-bound polycyclic aromatic hydrocarbons (PAHs) during the non-heating period, heating period, and haze period in Harbin, and infer their possible sources, and to evaluate their impact on population carcinogenesis. Methods From 2020 to 2022, sampling points were set up in different districts of Harbin. PM_2.5 samples were regularly collected every month to analyze the contents of 10 types of PM_2.5-bound 4-6 rings PAHs. The pollution characteristics of PAHs were analyzed during different monitoring periods (non-heating period, heating period, and haze period). The excess carcinogenesis risks of PM_2.5-bound PAHs were assessed according to the Technical Specifications for Health Risk Assessment of Ambient Air Pollution and the U. S. Environmental Protection Agency (US EPA) risk assessment method. The characteristic ratio method and the positive matrix factorization (PMF) model were used to infer the sources of PAHs. Results The median mass concentrations of ambient PM_2.5-bound 4-6 rings PAHs (ΣPAHs) during the non-heating period, heating period, and haze period were 6.44 ng/m³, 37.85 ng/m³, and 106.79 ng/m³, respectively. During the heating season and haze period, the concentrations of benzo[a]anthracene, benzo[k]fluoranthene, pyrene and fluoranthene were relatively high. The excess carcinogenic risks for ASF_>16, ASF_2-16 and ASF_<2 caused by exposure to PM_2.5-bound 4-6rings PAHs during the heating season were 2.34×10^-6, 1.82×10^-6, and 0.88×10^-6, respectively, while the excess carcinogenic risks for the whole population during the heating season and haze period were 5.05×10^-6 and 1.75×10^-6, respectively. The results of the two source methods showed that the main characteristic elements during the heating season were fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene. According to the emission source standards, it was determined that the sources were mainly coal and biomass combustion, accompanied by traffic source emissions. Conclusion In Harbin, the PM_2.5-bound 4-6 rings PAHs during the haze period is significantly higher than that during the heating period. The pollution is mainly from coal combustion emissions, accompanied by continuous traffic source pollution. The exposure to PAHs during the heating period poses a potential carcinogenic risk to the population.

ObjectiveTo investigate the patterns of chronic disease comorbidity among permanent elderly residents in Xuhui District of Shanghai, and to analyze the impact of different comorbidity patterns on the elderly’s ability to perform activities of daily living. MethodsBased on data from the 2015 and 2021 Surveys on Health Status and Health Service Utilization among Permanent Residents in Xuhui District of Shanghai, the study included permanent residents who fully participated in both surveys, were aged 60 years or older at the 2015 survey, self-reported having a chronic disease, and reported no significant changes in their chronic disease status between the two surveys. A prospective cohort study design was adopted, using the 2015 data as the baseline and the 2021 survey data as follow-up data. Physical examinations and questionnaire surveys were conducted by the Shanghai Xuhui District Center for Disease Control and Prevention in the subdistricts and towns within the jurisdiction from April to July in both 2015 and 2021. Latent class analysis (LCA) was used to classify comorbidity patterns across 11 types of chronic diseases. The smaller the values of the Akaike information criterion (AIC), the Bayesian information criterion (BIC), and the sample-corrected Bayesian information criterion (aBIC), the better the model fits. The Barthel index (BI) and the Lawton and Brody Instrumental Activities of Daily Living Scale (LB-IADL) were used to assess the participants’ activities of daily living (ADL) and instrumental activities of daily living (IADL). Multiple linear regression and multivariate logistic regression models were used to analyze the association between different comorbidity patterns and ADL and IADL. ResultsA total of 1 608 study participants were enrolled. Among them, 671 (41.73%) self-reported having no chronic diseases. The prevalence of 11 types of chronic diseases was as follows: hypertension in 743 participants (46.21%), heart disease in 148 participants (9.20%), cerebrovascular disease in 37 participants (2.30%), diabetes or abnormal blood glucose in 310 participants (19.28%), other endocrine system diseases (non-diabetic) in 39 participants (2.43%), malignant tumors in 37 participants (2.30%), chronic lung disease in 16 participants (1.00%), gout in 8 participants (0.50%), musculoskeletal disorders in 34 participants (2.11%), gastric or digestive system diseases in 27 participants (1.68%), and dyslipidemia in 15 participants (0.93%). LCA was used to classify comorbidity patterns of chronic diseases among older adults into 1 to 9 latent category combinations. Model 5 (i.e., 5 latent categories) had the lowest BIC (7 112.69) and aBIC (6 909.38), with a relatively low AIC (6 768.20), indicating the best model fit; thus, five latent categories represented the optimal combination in this study. The five latent categories (and their respective proportions of study participants) were the healthy control group (41.73%), the hypertension group (31.28%), the diabetes-hypertension group (19.28%), the severe illness group (5.29%), and the other metabolic diseases group (2.43%). According to multiple linear regression analyses, compared with the healthy control group, the diabetes-hypertension group had significantly lower BI-20 scores (b=-0.952, 95%CI: -1.317‒ -0.587, P<0.001) and lower IADL scores (b=-0.744, 95%CI: -0.999‒ -0.489, P<0.001); the severe illness group (b=-0.644, 95%CI: -1.072‒ -0.217, P=0.003) and the hypertension group (b=-0.344, 95%CI: -0.562‒ -0.125, P=0.002) had lower IADL scores. According to multivariate logistic regression analyses, compared with the healthy control group, older adults in the diabetes-hypertension group had a higher risk of disability (OR=2.835, 95%CI: 1.392‒5.774), impaired ADL function (OR=2.470, 95%CI: 1.637‒3.726), and impaired IADL function (OR=1.739, 95%CI: 1.264‒2.392); older adults in the severe illness group had a higher risk of impaired ADL function (OR=2.206, 95%CI: 1.171‒4.155). ConclusionAmong the elderly participating in the Survey on Health Status and Health Service Utilization of Permanent Residents in Xuhui District of Shanghai, diabetes-hypertension is one of the key chronic disease comorbidity combinations and has adverse effects on both ADL and IADL. Community health management should prioritize the elderly with diabetes-hypertension comorbidity, and strengthen early screening and comprehensive interventions to slow the decline in ADL and IADL.

Purpose To investigate the predictive value of the methylation regulator heterogeneous nuclear ribonu-cleoprotein C(HNRNPC)in the extracellular vesicles(EVs)derived from cervical cancer cells for tumor invasion and metastasis.Methods In vitro experiments were conducted using a human normal cervical epithelial cell line(Hcer-Epic),three cervical cancer cell lines(HeLa,SiHa and CaSki)and human umbilical vein endothelial cells(HU-VECs).HNRNPC protein expression was assessed by Western blot.CaSki cells were transfected with either sh-NC or sh-HNRNPC,and EVs were subsequently isolated from culture supernatant.The effects of EVs on the proliferation,migration and invasion of SiHa cells,as well as on angiogenesis in HUVECs,were investigated respectively.For tissue microarray analysis,normal cervical tissues(n=8),low-grade squamous intraepithelial lesions(LSIL,n=32)and high-grade squamous intraepithelial lesions(HSIL,n=37),and cervical carcinoma specimens(n=153)were ob-tained from our institution.Based on HNRNPC immunoscores,cervical cancer patients were divided into two groups:high(n=99)and low(n=54)HNRNPC expression group,and their clinicopathological features and prognosis were compared.Results Compared with HcerEpic cells,the expression of HNRNPC increased in SiHa,HeLa and CaSki cells.In SiHa cells treated with EVs from CaSki cell,the group receiving EVs from sh-HNRNPC-transfected CaSki cells showed significantly reduced proliferation,colony formation,migration,and invasion compared with the sh-NC-EVs group(P＜0.05).Similarly,in HUVECs treated with CaSki-EVs,compared with sh-NC-EVs group,the sh-HNRNPC-EVs group demonsteated significantly lower protein expression of PCNA and VEGFA and reduced angiogene-sis length(P＜0.05).HNRNPC expression gradually increased during the transformation of cervical epithelial cells(F=106.9,P＜0.001),and was significantlyelevated in HSIL and cervical cancer tissues compared with normal tis-sues(P＜0.001).Moreover,in cervical cancer,high HNRNPC expression was significantly related to poorer cellular differentiation,larger tumor size,parametrial and vaginal infiltration,advanced FIGO stage,and pelvic lymph node metastasis(P＜0.05).Kaplan-Meier analysis showed that that patients with high HNRNPC expression had significant-ly shorter overall survival post-surgery compared with those with low expression(P＜0.05).Conclusion EVs contai-ning HNRNPC contribute to cervical cancer progression by promoting tumor growth,invasion,and angiogenesis,there-by accelerating metastasis.In addition,high HNRNPC expression in cervical cancer tissue is related to poor prognosis of patients,indicating that EV-associated HNRNPC may serve as a potential therapeutic target.

Subunit 5B of constitutively photomorphogenic 9 signalosome(CSN5B)is an inhibitory factor for the biosynthesis of vitamin C in the L-galactose synthesis pathway in plants.To create mutants with richer vitamin C in tomato fruits,a dual-target vector of pKSE402-SlCSN5Bwas constructed and trans-formed into the breeding parent of 1912.Based on the molecular biological assay and DNA sequencing,17 transgenic positive lines were determined,and 6 lines of them were genetically mutated at the target site of SlCSN5B,with an editing efficiency of 35.3％.Among the mutants,2 lines were homozygous mu-tants,csn5b-6 with 180 bp deletion and csn5b-8 with 3 bp deletion.The biological traits of two types of deficiency homozygotes without exogenous T-DNA insertion derived from the T1 generation were observed,and there were no significant differences in phenotypes of the plant and fruit.Through physiological tes-ting of red-ripe fruits from T,generation lines of csn5b-6,the GMPase activity and the vitamin C content significantly increased by 43％and 37.8％,respectively,the content of hydrogen peroxide significantly decreased by 25.9％,and the content of soluble solids did not obviously change,compared with the wild type.There were no significant differences in plant traits and physiological characteristics between T1 gen-eration lines of csn5b-8 and the wild type.Based on gene expression analysis and protein structure predic-tion,the results showed that the gene of SlCSN5B normally transcribed,and the loss of large peptide seg-ments of CSN5B encoded by SlCSN5B caused changes in its structure to affect functioning,which led to an increase of vitamin C content in the line of csn5b-6-1 1.The findings suggest that the vitamin C content of tomato fruit can be improved by CRISPR/Cas9-mediated SlCSN5B gene editing,which provides the valuable resources for high-quality breeding in tomato.

Objective To investigate the relationship between ST-segment elevation myocardial infarction(STEMI)treatment time nodes and coronary microcirculation dysfunction(CMD)after primary percutaneous coronary intervention(PCI)and its prognosis,providing evidence for early identification of high-risk patients,further optimization of treatment system,shortening treatment time and improving prognosis.Methods This study selected 150 STEMI patients who received primary PCI at the 920th Hospital of the Joint Logistic Support Force of the People's Liberation Army of China from March 2023 to September 2023 as the CMD group after PCI(89 cases),with a microcirculation resistance index(caIMR)of≥40 U based on coronary angiography.caIMR＜40 U was classified as the non-CMD group(61 cases).The clinical data,various examination indicators and imaging data of the two groups of patients were collected,and the occurrence of major adverse cardiovascular events(MACE)within half a year after direct PCI of the patients was followed up.The correlation between the two variables was analyzed using Spearman.Multivariate Logistic regression was used to analyze the relationship between each treatment time point and the occurrence of CMD after direct PCI.Using receiver operating characteristic(ROC)curve analysis to predict the occurrence of CMD after direct PCI.The survival curves between the two groups were plotted using the Kaplan-Meier method.Results The levels of symptom onset-to-balloon(S-to-B),symptom onset-to-first medical contact(S-to-FMC),first medical contact-to-balloon(FMC-to-B),symptom onset-to-door(S-to-D)and first medical contact-to-door(FMC-to-D)in the CMD group were significantly higher than those in the non-CMD group(all P＜0.05).Correlation analysis showed that S-to-D,S-to-FMC,the time from FMC-to-B,and the time from FMC-to-D were all positively correlated with the time from S-to-B(r=0.996,P＜0.001;r=0.937,P＜0.001;r=0.431,P＜0.001;r=0.441,P＜0.001).Multivariate Logistic regression analysis indicated that the duration of S-to-D(OR 2.165,95％CI 1.655-2.830,P＜0.001)was a significant influencing factor for CMD.Moreover,S-to-D has a relatively high predictive value for the occurrence of CMD after direct PCI.The area under the ROC curve is 0.898(95％CI 0.850-0.946,P＜0.001),the optimal cut-off value is 231 min,the sensitivity is 82.0％,and the specificity is 88.5％.Kaplan-Meier curve analysis showed that the cumulative survival rate of MACE outcomes in the CMD group was significantly lower than that in the non-CMD group(Log-rank P=0.009).Conclusions Shortening the S-to-D time can reduce the occurrence of CMD after PCI,thereby reducing the incidence of MACE and improving prognosis.