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With the rapid development of immunotherapy, therapeutic tumor vaccines, which aim to enhance the immunogenicity of tumor cells and activate the patient's immune system to kill tumor cells, as well as eliminate or inhibit tumor growth, have drawn increasing attention in the field of tumor therapy. However, due to the lack of immune cell infiltration, low immunogenicity, immune escape and other problems, the efficacy of tumor vaccine is often limited. Researchers have developed a variety of strategies to enhance tumor immune recognition, such as improving the immunogenicity of tumor antigens, selecting a suitable vaccine platform, or combining tumor vaccines with other anticancer treatments. In this review, we will deliberate on how to overcome the problem of therapeutic tumor vaccines, and discuss the up-to-date progress and achievements in the tumor vaccine development, as well as their future in cancer treatment.
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Background: The ryanodine receptor 3 (RYR3) is involved in skeletal muscle contraction by releasing calcium from the sarcoplasmic reticulum and subsequent T-tubule depolarization. It is also expressed in the brain, and variants in the RYR3 gene can lead to congenital myopathy type 20 (MIM: #620310). Methods: We retrospectively analyzed the clinical characteristics and prognosis of a case of West syndrome, developmental and epileptic encephalopathy (DEE) caused by a missense variant in the RYR3 gene. We also reviewed and summarized the literature on epilepsy cases caused by RYR3 gene variants. Results: A 10-month-old female child with delayed psychomotor development and recurrent spasm-like seizures was diagnosed with infantile spasm syndrome and DEE. Treatment with various antiepileptic drugs resulted in initial improvement but ultimately failed to control the seizures. Whole-exome sequencing revealed a novel heterozygous variant c.10943C > T/p.T3648M in the RYR3 gene, and genome-wide sequencing ruled out other potentially pathogenic variants. Three previous reports have described RYR3 variants causing DEE, two of which were attributed to de novo heterozygous variants, and one was a compound heterozygote. Conclusion: The present case of DEE caused by a RYR3 heterozygous variant is consistent with previous rare cases of epilepsy caused by RYR3 gene variants in terms of pathogenesis and clinical features, but significantly different from congenital myopathy type 20. Our findings provide important evidence for the diagnosis of RYR3-related DEE, and we hypothesize that RYR3 gain-of-function variants resulting in "leaky" Ca2+ release channels may be a molecular genetic feature leading to DEE rather than myopathy.
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The development of an affordable, portable, and instrument-free colorimetric biosensor holds significant importance for routine monitoring and clinical diagnosis. To overcome the limitations that traditional monochromatic colorimetric kits struggle to distinguish subtle color changes with the naked eye, we designed and constructed a portable hydrogel kit for polychromatic semi-quantitative and quantitative sensing analysis. When the actual samples and I- were introduced into a gelatin hydrogel encapsulated with MIL-88A(Fe), Au NRs and oxidase (Au@GM88A/I), a noticeable color change occurred. Additionally, a mathematic model between Hue and multicolor signal was set up for the first time by mobile phone photo technology, successfully applied to the glucose detection in serum. The visual detection had a wide concentration range of 0.02-0.80â¯mM with a limit of detection down to 0.02â¯mM. Above all, hydrogel kit prepared with gelatin as a carrier addressed the issues of uneven color and slow response rate commonly seen in gels like sodium alginate and agarose. This improvement would be beneficial for enhancing the accuracy of color captured by mobile phone assisted hydrogel kits, making it a valuable tool for biomarker analysis.
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Copper ions, implicated in processes such as oxidative stress and inflammation, are believed to play a crucial role in cardiovascular disease, a prevalent and deadly disease. Despite this, current diagnostic methods fail to detect early stage cardiovascular disease or track copper ion accumulation, limiting our understanding of the disease's progression. Therefore, the development of noninvasive techniques to image copper ions in cardiovascular disease is urgently needed to enhance diagnostic precision and therapeutic strategies. In this study, we report the successful synthesis and application of a copper ion-activated photoacoustic probe, CS-Cu, which exhibits high sensitivity and selectivity toward copper ions both in vitro and in vivo. CS-Cu was able to noninvasively monitor the changes in copper ion levels and differentiate between different mice based on copper ions in urine. Furthermore, the probe demonstrated good photoacoustic stability and exhibited no significant toxicity in the mice. These findings suggest that CS-Cu could be a promising tool for early detection and monitoring of Cu2+ levels in vivo and urine, providing a new perspective on the role of copper ions in cardiovascular disease.
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This study systematically evaluated and ranked the efficacy of first- and second-line antibiotics antibiotic options for the clinical management of cellulitis and erysipelas through a network meta-analysis approach. From inception to July 04, 2024, a search for relevant randomized clinical trials (RCTs) was carried out using several databases. Antibiotics including azithromycin, cefaclor, cephalexin, cloxacillin, erythromycin, cephalexin plus trimethoprim-sulfamethoxazole, cephalexin plus placebo, flucloxacillin, clindamycin, ceftriaxone, penicillin, roxithromycin, and pristinamycin were assessed regarding cure rate, the eradication of baseline pathogens, diarrhea or vomiting, and rash. In total, 10 RCTs with 1,936 cellulitis or erysipelas patients were eligible for inclusion. There were no significant differences in the cure rates for cellulitis among the antibiotics analysed, with cefaclor demonstrating the most favorable profile for curative outcomes. In terms of side effects, ceftriaxone was identified as the least likely to induce diarrhea or vomiting. For erysipelas, pristinamycin showed the most promising results in achieving cure rates. Although a comparison of the three antibiotics revealed no significant differences in rash as a side effect in erysipelas, pristinamycin was observed to carry the highest risk for rash. Our findings indicate no significant differences in cure rates among antibiotics for cellulitis. However, ceftriaxone had the fewest gastrointestinal side effects. Pristinamycin showed the highest cure rates for erysipelas but with a higher risk of rash. Future research should focus on optimizing antibiotic selection for cellulitis and erysipelas.
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Antibacterianos , Celulite (Flegmão) , Erisipela , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Erisipela/tratamento farmacológico , Celulite (Flegmão)/tratamento farmacológico , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Resultado do Tratamento , Pristinamicina/efeitos adversos , Pristinamicina/uso terapêuticoRESUMO
In situ vaccines that can stimulate tumor immune response have emerged as a breakthrough in antitumor therapy. However, the immunosuppressed tumor microenvironment and insufficient infiltration of immune cells lead to ineffective antitumor immunity. Hence, a biomimetic carrier-free nanosystem (BCC) to induce synergistic phototherapy/chemotherapy-driven in situ vaccines was designed. A carrier-free nanosystem was developed using phototherapeutic reagents CyI and celastrol as raw materials. In vitro and in vivo studies have shown that under NIR light irradiation, BCC-mediated photo/chemotherapy not only accelerates the release of drugs to deeper parts of tumors, achieving timing and light-controlled drug delivery to result in cell apoptosis, but also effectively stimulates the antitumor response to induce in situ vaccine, which could invoke long-lasting antitumor immunity to inhibit tumor metastasis and eliminate distant tumor. This therapeutic strategy holds promise for priming robust innate and adaptive immune responses, arresting cancer progression, and inducing tumor dormancy.
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Recent years, edge-cloud computing has attracted more and more attention due to benefits from the combination of edge and cloud computing. Task scheduling is still one of the major challenges for improving service quality and resource efficiency of edge-clouds. Though several researches have studied on the scheduling problem, there remains issues needed to be addressed for their applications, e.g., ignoring resource heterogeneity, focusing on only one kind of requests. Therefore, in this paper, we aim at providing a heterogeneity aware task scheduling algorithm to improve task completion rate and resource utilization for edge-clouds with deadline constraints. Due to NP-hardness of the scheduling problem, we exploit genetic algorithm (GA), one of the most representative and widely used meta-heuristic algorithms, to solve the problem considering task completion rate and resource utilization as major and minor optimization objectives, respectively. In our GA-based scheduling algorithm, a gene indicates which resource that its corresponding task is processed by. To improve the performance of GA, we propose to exploit a skew mutation operator where genes are associated to resource heterogeneity during the population evolution. We conduct extensive experiments to evaluate the performance of our algorithm, and results verify the performance superiority of our algorithm in task completion rate, compared with other thirteen classical and up-to-date scheduling algorithms.
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BACKGROUND: Previous studies have demonstrated the benefits of ideal cardiovascular health (CVH) in reducing cardiovascular risk. However, its role in subclinical atherosclerosis (SA) progression remains unclear. We aim to examine the association of CVH, estimated by the American Heart Association's new Life's Essential 8 (LE8), with the progression of SA. METHODS: This prospective cohort study was conducted among 972 asymptomatic Chinese participants and followed up for 5.7 years. The LE8 score (range, 0-100) consisted of blood pressure, lipids, glucose, body mass index, smoking status, diet health, physical activity and sleep health was evaluated in 1998 and 2008-2009. Progression of SA was determined by carotid plaque and coronary artery calcification (CAC) in 2008-2009 and 2013-2014. Log-binomial regression model was used to estimate the association of LE8 score with SA progression. RESULTS: Each 10 points increment in LE8 score was associated with 15.2% (RR: 0.848, 95% CI: 0.797-0.902), 17.7% (RR: 0.823, 95% CI: 0.766-0.884) and 12.0% (RR: 0.880, 95% CI: 0.845-0.916) lower risks of carotid plaque, CAC and overall SA progression, respectively. Compared with participants with non-ideal CVH at both visits, the participants with ideal CVH at both visits had 39.1% (RR: 0.609, 95% CI: 0.494-0.752), 41.0% (RR: 0.590, 95% CI: 0.456-0.764) and 29.7% (RR: 0.703, 95% CI: 0.598-0.825) lower risks of carotid plaque, CAC and overall SA progression, respectively. CONCLUSIONS: Higher LE8 scores were associated with lower risks of SA progression. Besides, long-term maintenance of optimal CVH was more beneficial to prevent SA progression.
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Hepatocellular carcinoma (HCC) is a leading cause of cancer-associated death globally. Liver transplantation (LT) has emerged as a key treatment for patients with HCC, and the Milan criteria have been adopted as the cornerstone of the selection policy. To allow more patients to benefit from LT, a number of expanded criteria have been proposed, many of which use radiologic morphological characteristics with larger and more tumors as surrogates to predict outcomes. Other groups developed indices incorporating biological variables and dynamic markers of response to locoregional treatment. These expanded selection criteria achieved satisfactory results with limited liver supplies. In addition, a number of prognostic models have been developed using clinicopathological characteristics, imaging radiomics features, genetic data, and advanced techniques such as artificial intelligence. These models could improve prognostic estimation, establish surveillance strategies, and bolster long-term outcomes in patients with HCC. In this study, we reviewed the latest findings and achievements regarding the selection criteria and post-transplant prognostic models for LT in patients with HCC.
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OBJECTIVE: To explore the efficacy and tolerability of high-frequency repetitive transcranial magnetic stimulation (rTMS) in the treatment of post-stroke working memory (WM) impairment and its changes in brain function. METHODS: In the present randomized, double-blinded, sham-controlled design, 10 Hz rTMS was administered to the left dorsolateral prefrontal cortex (DLPFC) of patients with post-stroke WM impairment for 14 days. Measures included WM (primary outcome), comprehensive neuropsychological tests, and the functional near-infrared spectroscopy test. Patients were assessed at baseline, after the intervention (week 2), and 4 weeks after treatment cessation (week 6). RESULTS: Of 123 stroke patients, 82 finished the trial. The rTMS group showed more WM improvement at week 2 (t = 5.55, P < .001) and week 6 (t = 2.11, P = .045) than the sham group. Most of the neuropsychological test scores were markedly improved in the rTMS group. In particular, the rTMS group exhibited significantly higher oxygenated hemoglobin content and significantly stronger functional connectivity in the left DLPFC, right pre-motor cortex (PMC), and right superior parietal lobule (SPL) at weeks 2 and 6. Dropout rates were equal (18% [9/50 cases] in each group), and headaches were the most common side effect (rTMS: 36% [18/50 cases]; sham: 30% [15/50 cases]). CONCLUSIONS: High-frequency rTMS was effective in improving post-stroke WM impairment, with good tolerability, and the efficacy lasted up to 4 weeks, which may be due to the activation of the left DLPFC, right PMC, and right SPL brain regions and their synergistic enhancement of neural remodeling.
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Transfection is an experimental technique typically used in biological experiments. In this study, we verified whether this technique may cause the release of inflammatory cytokines and affect cell viability. We used lipopolysaccharide (LPS)-induced human bronchial epithelial (16-HBE) cells as a model to evaluate whether cell transfection with Lipofectamine 3000 would affect LPS-induced inflammatory factors in HBE cells. MicroRNA (miRNA) negative control (NC)- and miR-584-mimics were transfected into 16-HBE cell lines. The 584-mimic was used to increase the expression of miR-584, and the NC-mimic was used to add a negative control sequence. After 24h of transfection, the cells were incubated with LPS for another 24h, and the effects on the release of inflammatory cytokines, such as IL-1, IL-6, IL-8, TNF-α, MIP-1, MCP-1α, and cell viability were investigated. The optimal conditions for transfection were evaluated, and cytokine and chemokine mRNA levels were determined. Regardless of the NC- or 584-mimic, the results indicate that the expression of transfected genes in these cells leads to an increase in inflammatory factors and decreased cell viability. Microscope analysis revealed that the number of HBE cells was lower after transfection, and many small vesicles could be observed in the transfected cells, indicating that the insertion of gene vectors may affect the biological activity of HBE cells and experimental results. Results suggest that Lipofectamine 3000 transfected miRNA into HBE cells, providing better transfection rates, however, at the cost of higher toxicity.
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Given the critical role of dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mouse models in the appraisal of associated therapeutic drugs, the optimization of the administration method and dosages is of paramount importance. Therefore, UC was induced in mice through the gavage administration of a DSS solution instead of free drinking water. The effects of varying daily dosages (2, 4, 6, and 8 g/kg) and frequencies (once or twice) of administration on the body weight and survival rate of the model mice were evaluated. Concurrently, the inflammatory indicators and tissue sections of the model mice were thoroughly evaluated. The results revealed that when the daily dosage reached 8 g/kg, the dosage exhibited a high level of toxicity, resulting in a high mortality rate among the mice. The DSS administration of 6 g/kg*2 not only elicited conspicuous symptoms, significant weight loss, substantial shortening of the colon, and significant changes in various inflammatory indicators, such as myeloperoxidase (MPO), nitric oxide (NO), reactive oxygen species (ROS), and glutathione (GSH), but it also maintained a high survival rate in the UC mice. The findings from this experiment lay a solid experimental foundation for future research on drugs intended for the treatment of UC.
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Deep vein thrombosis (DVT) is a serious health issue that often leads to considerable morbidity and mortality. Diagnosis of DVT in a clinical setting, however, presents considerable challenges. The fusion of metabolomics techniques and machine learning methods has led to high diagnostic and prognostic accuracy for various pathological conditions. This study explored the synergistic potential of dual-platform metabolomics (specifically, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS)) to expand the detection of metabolites and improve the precision of DVT diagnosis. Sixty-one differential metabolites were identified in serum from DVT patients: 22 from GC-MS and 39 from LC-MS. Among these, five key metabolites were highlighted by SHapley Additive exPlanations (SHAP)-guided feature engineering and then used to develop a stacking diagnostic model. Additionally, a user-friendly interface application system was developed to streamline and automate the application of the diagnostic model, enhancing its practicality and accessibility for clinical use. This work showed that the integration of dual-platform metabolomics with a stacking machine learning model enables faster and more accurate diagnosis of DVT in clinical environments.
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Yeast has been extensively studied and engineered due to its genetic amenability. Projects like Sc2.0 and Sc3.0 have demonstrated the feasibility of constructing synthetic yeast genomes, yielding promising results in both research and industrial applications. In contrast, plant synthetic genomics has faced challenges due to the complexity of plant genomes. However, recent advancements of the project SynMoss, utilizing the model moss plant Physcomitrium patens, offer opportunities for plant synthetic genomics. The shared characteristics between P. patens and yeast, such as high homologous recombination rates and dominant haploid life cycle, enable researchers to manipulate P. patens genomes similarly, opening promising avenues for research and application in plant synthetic biology. In conclusion, harnessing insights from yeast synthetic genomics and applying them to plants, with P. patens as a breakthrough, shows great potential for revolutionizing plant synthetic genomics.
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BACKGROUND: Long non-coding RNAs (LncRNAs) have been implicated as critical regulators of cancer tumorigenesis and progression. However, their functions and molecular mechanisms in colorectal cancer (CRC) still remain to be further elucidated. METHODS: LINC00460 was identified by differential analysis between human CRC and normal tissues and verified by in situ hybridization (ISH) and qRT-PCR. We investigated the biological functions of LINC00460 in CRC by in vitro and in vivo experiments. We predicted the mechanism and downstream functional molecules of LINC00460 by bioinformatics analysis, and confirmed them by dual luciferase reporter gene assay, RNA immunoprecipitation (RIP), RNA pull-down, etc. RESULTS: LINC00460 was found to be significantly overexpressed in CRC and associated with poor prognosis. Overexpression of LINC00460 promoted CRC cell immune escape and remodeled a suppressive tumor immune microenvironment, thereby promoting CRC proliferation and metastasis. Mechanistic studies showed that LINC00460 served as a molecular sponge for miR-186-3p, and then promoted the expressions of MYC, CD47 and PD-L1 to facilitate CRC cell immune escape. We also demonstrated that MYC upregulated LINC00460 expression at the transcriptional level and formed a positive feedback loop. CONCLUSIONS: The LINC00460/miR-186-3p/MYC feedback loop promotes CRC cell immune escape and subsequently facilitates CRC proliferation and metastasis. Our findings provide novel insight into LINC00460 as a CRC immune regulator, and provide a potential therapeutic target for CRC patients.
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Antígeno B7-H1 , Antígeno CD47 , Neoplasias Colorretais , MicroRNAs , RNA Longo não Codificante , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/imunologia , MicroRNAs/genética , Antígeno CD47/metabolismo , Antígeno CD47/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Camundongos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Animais , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Evasão Tumoral/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Masculino , Feminino , Proliferação de Células , Retroalimentação Fisiológica , Prognóstico , Camundongos NusRESUMO
Large field-of-view images are increasingly used in various environments today, and image stitching technology can make up for the limited field of view caused by hardware design. However, previous methods are constrained in various environments. In this paper, we propose a method that combines the powerful feature extraction capabilities of the Superpoint algorithm and the exact feature matching capabilities of the Lightglue algorithm with the image fusion algorithm of Unsupervised Deep Image Stitching (UDIS). Our proposed method effectively improves the situation where the linear structure is distorted and the resolution is low in the stitching results of the UDIS algorithm. On this basis, we make up for the shortcomings of the UDIS fusion algorithm. For stitching fractures of UDIS in some complex situations, we optimize the loss function of UDIS. We use a second-order differential Laplacian operator to replace the difference in the horizontal and vertical directions to emphasize the continuity of the structural edges during training. Combined with the above improvements, the Super Unsupervised Deep Image Stitching (SuperUDIS) algorithm is finally formed. SuperUDIS has better performance in both qualitative and quantitative evaluations compared to the UDIS algorithm, with the PSNR index increasing by 0.5 on average and the SSIM index increasing by 0.02 on average. Moreover, the proposed method is more robust in complex environments with large color differences or multi-linear structures.
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Dietary fatty acids (FAs) determine the quality of dairy products. The trans-10, cis-12 conjugated linoleic acid (t10c12-CLA) is commonly considered an FA factor leading to milk fat depression syndrome (MFDs) in dairy cow. However, its effect on dairy cow performance and involvement in milk fat metabolism have been insufficiently explored. This study administered 136.17 g/day of rumen-protected CLA (RP-CLA) to dairy cows and found a diminution in milk fat percentage and a trend of increasing milk protein percentage on day 21 postpartum. Lactose content, milk yield, and net energy for lactation were unaffected. In the cell experiments, Oil Red O staining showed a notable increase in lipid droplets. Gene and protein expression analysis showed that 300 µM t10c12-CLA upregulated the expression of CD36, DGAT2, and ADRP, while downregulating the expression of ACACA, FASN, SREBP1, FABP3, FATP3, ACSL4, LPIN1, DGAT1, BTN1A1, XDH, SNAP23, and VAMP4. This provides a possible mechanistic pathway for the contradictory phenomenon of t10c12-CLA reducing milk fat while increasing lipid droplets. Overall, t10c12-CLA, as a long-chain fatty acid, can promote lipid droplet synthesis but may reduce milk fat by inhibiting lipid droplet fusion and secretion, FAs de novo synthesis, and triglyceride biosynthesis.
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Background: Lymph node status is a prominent prognostic factor for intrahepatic cholangiocarcinoma (ICC). However, the prognostic value of performing lymph node dissection (LND) in patients with clinical node-negative ICC remains controversial. The aim of this study was to evaluate the clinical value of LND on long-term outcomes in this subgroup of patients. Methods: We retrospectively analyzed patients who underwent radical liver resection for clinically node-negative ICC from three tertiary hepatobiliary centers. The propensity score matching analysis at 1:1 ratio based on clinicopathological data was conducted between patients with and without LND. Recurrence-free survival (RFS) and overall survival (OS) were compared in the matched cohort. Results: Among 303 patients who underwent radical liver resection for ICC, 48 patients with clinically positive nodes were excluded, and a total of 159 clinically node-negative ICC patients were finally eligible for the study, with 102 in the LND group and 57 in the non-LND group. After propensity score matching, two well-balanced groups of 51 patients each were analyzed. No significant difference of median RFS (12.0 vs. 10.0 months, P = 0.37) and median OS (22.0 vs. 26.0 months, P = 0.47) was observed between the LND and non-LND group. Also, LND was not identified as one of the independent risks for survival. Among 51 patients who received LND, 11 patients were with positive lymph nodes (lymph node metastasis (LNM) (+)) and presented significantly worse outcomes than those with LND (-). On the other hand, postoperative adjuvant therapy was the independent risk factor for both RFS (hazard ratio (HR): 0.623, 95% confidence interval (CI): 0.393 - 0.987, P = 0.044) and OS (HR: 0.585, 95% CI: 0.359 - 0.952, P = 0.031). Furthermore, postoperative adjuvant therapy was associated with prolonged survivals of non-LND patients (P = 0.02 for RFS and P = 0.03 for OS). Conclusions: Based on the data, we found that LND did not significantly improve the prognosis of patients with clinically node-negative ICC. Postoperative adjuvant therapy was associated with prolonged survival of ICC patients, especially in non-LND individuals.
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Vernicia montana is a dioecious plant widely cultivated for high-quality tung oil production and ornamental purposes in the Euphorbiaceae family. The lack of genomic information has severely hindered molecular breeding for genetic improvement and early sex identification in V. montana. Here, we present a chromosome-level reference genome of a male V. montana with a total size of 1.29 Gb and a contig N50 of 3.69 Mb. Genome analysis revealed that different repeat lineages drove the expansion of genome size. The model of chromosome evolution in the Euphorbiaceae family suggests that polyploidization-induced genomic structural variation reshaped the chromosome structure, giving rise to the diverse modern chromosomes. Based on whole-genome resequencing data and analyses of selective sweep and genetic diversity, several genes associated with stress resistance and flavonoid synthesis such as CYP450 genes and members of the LRR-RLK family, were identified and presumed to have been selected during the evolutionary process. Genome-wide association studies were conducted and a putative sex-linked insertion and deletion (InDel) (Chr 2: 102 799 917-102 799 933 bp) was identified and developed as a polymorphic molecular marker capable of effectively detecting the gender of V. montana. This InDel is located in the second intron of VmBASS4, suggesting a possible role of VmBASS4 in sex determination in V. montana. This study sheds light on the genome evolution and sex identification of V. montana, which will facilitate research on the development of agronomically important traits and genomics-assisted breeding.
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Background: Despite the adverse effects of ambient fine particulate matter (PM2.5) on type 2 diabetes and the beneficial role of physical activity (PA), the influence of PM2.5 on the relationship between PA and type 2 diabetes remains unclear. Methods: In this prospective study with 71,689 participants, PA was assessed by a questionnaire and was categorized into quartiles for volume and three groups for intensity. Long-term PM2.5 exposure was calculated using 1-km resolution satellite-based PM2.5 estimates. PM2.5 exposure and PA's effect on type 2 diabetes were assessed by cohort-stratified Cox proportional hazards models, individually and in combination. Results: In 488,166 person-years of follow-up, 5487 incident type 2 diabetes cases were observed. The association between PA and type 2 diabetes was modified by PM2.5. Compared with the lowest quartile of PA volume, the highest quartile was associated with reduced type 2 diabetes risk in low PM2.5 stratification (≤65.02 µg/m3) other than in high PM2.5 stratification (>65.02 µg/m3), with the hazard ratio (HR) of 0.75 (95% confidence interval [CI]: 0.66-0.85) and 1.10 (95% CI: 0.99-1.22), respectively. Similar results were observed for PA intensity. High PM2.5 exposure combined with the highest PA levels increased the risk of type 2 diabetes the most (HR = 1.79, 95% CI: 1.59-2.01 for PA volume; HR = 1.82, 95% CI: 1.64-2.02 for PA intensity). Conclusion: PA could reduce type 2 diabetes risk in low-pollution areas, but high PM2.5 exposure may weaken or even reverse the protective effects of PA. Safety and health benefits of PA should be thoroughly assessed for long-term polluted residents.