Neurological disorders such as post-stroke hemiplegia, spinal cord injury, and Parkinson disease represent a major global health burden. Brain-computer interface (BCI), which creates direct communication pathways between the nervous system and external devices, offers a promising strategy for functional restoration. The long-term efficacy of such BCI fundamentally depends on the performance of biomaterials at the neural interface. Ideal materials must concurrently satisfy biocompatibility, electrical conductivity, enduring chemical stability, and mechanical compatibility with brain tissue. This review systematically outlines the application of conductive polymers, inorganic nanomaterials, natural biomaterials, and composites in BCI, with a focus on how advanced designs, such as bionic and encapsulated electrodes, improve signal fidelity and surgical feasibility through structural innovation. It further summarizes key material-modification techniques and analyzes the complex foreign-body response orchestrated by microglia, astrocytes, and peripheral immune cells. Finally, it provides insights into future research directions and clinical translation of BCI-based neurorehabilitation, while highlighting critical challenges including long-term biosafety and the establishment of standardized evaluation frameworks, aiming to bridge the gap between laboratory innovation and effective clinical deployment.

Objective To explore the differences in heartbeat-evoked response (HER) under drug-related cues and neutral cues in individuals with heroin use disorder (HUD), and analyze the correlation between HER potentials and immediate cue-induced craving scores. Methods Fifty HUD participants were recruited from the Chang’an Compulsory Isolation Drug Rehabilitation Center in Shaanxi Province from June to September 2024. Simultaneous acquisition of 64-channel electroencephalography (EEG) and electrocardiogram signals was performed. Twenty alternating segments of drug-related and neutral cue videos were presented, and participants rated their subjective craving after each segment using visual analogue scale (VAS) scores. Scalp EEG data were source analyzed to obtain cortical EEG signals and corresponding HER. Short-time Fourier transform was used to calculate the power spectral density (PSD) of EEG within a time window from 100 ms before the R-peak to 500 ms after it, using the R-peak as the time zero point. Cluster-based permutation testing was used to analyze PSD differences between drug-related and neutral cues in the HUD individuals. Pearson correlation analysis was performed to evaluate the correlation between HER potentials and VAS scores. Results In the 350–420 ms time window, HER potentials in the left posterior parietal, temporal, and posterior cingulate cortices were significantly lower under drug-related cues compared to neutral cues (P＜0.01); in the 140–210 ms time window, HER potentials in the right prefrontal cortex were significantly higher under drug-related cues compared to neutral cues (P＜0.01). Correlation analysis showed that HER potentials in the left temporal and left posterior cingulate cortices were significantly negatively correlated with VAS scores (P＜0.05). Drug-related cues enhanced PSD of γ power (30–100 Hz) in salience network (fronto-insular), parietal and occipital regions (P＜0.05). PSD integrations of low-γ power (40–60 Hz) in parietal region (350–400 ms) and high-γ power (70–100 Hz) in left salience network (fronto-parietal) and occipital regions (300–350 ms) were positively correlated with VAS scores (P＜0.05). Conclusions Drug-related cues may modulate cortical activity related to heartbeat perception in HUD individuals, and such dynamic changes in both time and frequency domains are stably associated with subjective craving.

ObjectiveTo investigate whether Huanglian Jiedutang can inhibit neutrophil infiltration in the brains of middle cerebral artery occlusion （MCAO） mice by regulating the expression of neutrophil-related chemokines in exosomes， thereby achieving therapeutic effects. MethodsA total of 130 male specific pathogen-free （SPF） C57BL/6J mice were randomly divided into four groups： Sham-operated group， MCAO model group， Huanglian Jiedutang group （6 g·kg^-1）， and Ginaton group （21.6 mg·kg^-1）， with 10 mice in the Ginaton group and 40 mice in each of the remaining three groups. Mice in the Huanglian Jiedutang group and the Ginaton group were administered the corresponding drugs by oral gavage once daily at a volume of 0.15 mL·（10 g）^-1 for 7 consecutive days， while the sham-operated and model groups received an equal volume of saline via the same route. After 7 days， MCAO surgery was performed. The distal and proximal ends of the right common carotid artery （CCA） were ligated， a small incision was made between the two ligatures， and a silicone rubber-coated monofilament with a rounded tip was inserted into the lumen to occlude the CCA. The filament was left in place for 1 h to establish a focal cerebral ischemia model. At 24 h after modeling， mice were evaluated. Neurological function was assessed using the Longa score. Cerebral infarct volume was measured by 2，3，5-triphenyltetrazolium chloride （TTC） staining. Cerebral blood flow was observed by laser speckle imaging. Hematoxylin and eosin （HE） staining and Nissl staining were used to observe pathological changes in brain tissues. Exosomes were isolated from mouse plasma and brain tissues by ultracentrifugation and molecular size exclusion and identified by electron microscopy， particle size analysis， and protein blotting. Long-chain RNA libraries of exosomes were constructed and sequenced. Real-time quantitative reverse transcription polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of inflammatory factors and neutrophil-related chemokines in exosomes from plasma and brain tissues of each group. Enzyme-linked immunosorbent assay （ELISA） was used to detect the protein expression of inflammatory factors and neutrophil-related chemokines in exosomes from brain tissues of each group. Immunohistochemistry was used to detect the expression of the neutrophil-specific protein myeloperoxidase （MPO） in the brains of mice in each group. ResultsCompared with the sham-operated group， the model group showed decreased neurological function scores （P<0.01）， obvious cerebral infarction （P<0.01）， reduced cerebral blood flow （P<0.01）， neuronal necrosis in the brain， and decreased numbers of Nissl bodies （P<0.01）. The mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were significantly increased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were increased （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were elevated （P<0.01）. Compared with the model group， the Huanglian Jiedutang group and the Ginaton group showed increased neurological function scores （P<0.05）， reduced cerebral infarct volume （P<0.01）， restored cerebral blood flow （P<0.01）， reduced necrotic cells in the brain， and increased numbers of Nissl bodies （P<0.01）. In the Huanglian Jiedutang group， the mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were decreased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were reduced （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were decreased （P<0.01）. ConclusionHuanglian Jiedutang can effectively regulate the expression of neutrophil-related chemokines in exosomes from plasma and brain tissues of MCAO mice， thereby reducing neutrophil infiltration in the brain and achieving therapeutic effects.

ObjectiveTo investigate whether Huanglian Jiedutang can inhibit neutrophil infiltration in the brains of middle cerebral artery occlusion （MCAO） mice by regulating the expression of neutrophil-related chemokines in exosomes， thereby achieving therapeutic effects. MethodsA total of 130 male specific pathogen-free （SPF） C57BL/6J mice were randomly divided into four groups： Sham-operated group， MCAO model group， Huanglian Jiedutang group （6 g·kg^-1）， and Ginaton group （21.6 mg·kg^-1）， with 10 mice in the Ginaton group and 40 mice in each of the remaining three groups. Mice in the Huanglian Jiedutang group and the Ginaton group were administered the corresponding drugs by oral gavage once daily at a volume of 0.15 mL·（10 g）^-1 for 7 consecutive days， while the sham-operated and model groups received an equal volume of saline via the same route. After 7 days， MCAO surgery was performed. The distal and proximal ends of the right common carotid artery （CCA） were ligated， a small incision was made between the two ligatures， and a silicone rubber-coated monofilament with a rounded tip was inserted into the lumen to occlude the CCA. The filament was left in place for 1 h to establish a focal cerebral ischemia model. At 24 h after modeling， mice were evaluated. Neurological function was assessed using the Longa score. Cerebral infarct volume was measured by 2，3，5-triphenyltetrazolium chloride （TTC） staining. Cerebral blood flow was observed by laser speckle imaging. Hematoxylin and eosin （HE） staining and Nissl staining were used to observe pathological changes in brain tissues. Exosomes were isolated from mouse plasma and brain tissues by ultracentrifugation and molecular size exclusion and identified by electron microscopy， particle size analysis， and protein blotting. Long-chain RNA libraries of exosomes were constructed and sequenced. Real-time quantitative reverse transcription polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of inflammatory factors and neutrophil-related chemokines in exosomes from plasma and brain tissues of each group. Enzyme-linked immunosorbent assay （ELISA） was used to detect the protein expression of inflammatory factors and neutrophil-related chemokines in exosomes from brain tissues of each group. Immunohistochemistry was used to detect the expression of the neutrophil-specific protein myeloperoxidase （MPO） in the brains of mice in each group. ResultsCompared with the sham-operated group， the model group showed decreased neurological function scores （P<0.01）， obvious cerebral infarction （P<0.01）， reduced cerebral blood flow （P<0.01）， neuronal necrosis in the brain， and decreased numbers of Nissl bodies （P<0.01）. The mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were significantly increased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were increased （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were elevated （P<0.01）. Compared with the model group， the Huanglian Jiedutang group and the Ginaton group showed increased neurological function scores （P<0.05）， reduced cerebral infarct volume （P<0.01）， restored cerebral blood flow （P<0.01）， reduced necrotic cells in the brain， and increased numbers of Nissl bodies （P<0.01）. In the Huanglian Jiedutang group， the mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were decreased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were reduced （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were decreased （P<0.01）. ConclusionHuanglian Jiedutang can effectively regulate the expression of neutrophil-related chemokines in exosomes from plasma and brain tissues of MCAO mice， thereby reducing neutrophil infiltration in the brain and achieving therapeutic effects.

ObjectiveTo investigate whether Huanglian Jiedutang （HLJD） and its major active constituents （geniposide， baicalin， and berberine） can inhibit the inflammatory response of BV2 cells under lipopolysaccharide （LPS） stimulation via the high-mobility group protein B1 （HMGB1）/Toll-like receptor 4 （TLR4）/nuclear factor-κB （NF-κB） signaling pathway， and to explore differences in therapeutic efficacy among the three monomers， their combined formula， and HLJD under equal content ratios. MethodsBV2 microglial cells were used as the primary experimental model. Cell viability was assessed using the cell counting kit-8 （CCK-8） method to examine the effects of different concentrations of dimethyl sulfoxide （DMSO， 0.8%， 0.4%， 0.2%， 0.1%， and 0.05%） on cell viability. IncuCyte was employed to monitor the growth of cells under different concentrations of HLJD （200， 100， 50， 25， 12.5， 6.25 mg·L^-1）. Nitric oxide （NO） assay was used to screen the optimal HLJD concentration. High-performance liquid chromatography （HPLC） determined the content of geniposide， baicalin， and berberine in HLJD， and experimental groups were subsequently established according to the relative proportions of these constituents. CCK-8 assay evaluated cell viability under different treatments. Enzyme-linked immunosorbent assay （ELISA） measured levels of inflammatory factors （TNF-α， IL-1β， IL-6， IL-10） in the supernatant. Flow cytometry assessed the effects of treatments on M1-type polarization of BV2 cells. Western blot determined the expression levels of HMGB1， TLR4， and NF-κB-related proteins. ResultsCompared with the blank group， DMSO at concentrations ≤0.2% did not affect cell viability within 48 h. BV2 cell growth plateaued at 24 h after treatment with 200 mg·L^-1 HLJD. Under stimulation with 2 mg·L^-1 LPS， this concentration of HLJD effectively reduced NO release， and 6 h pre-treatment had a stronger inhibitory effect on NO than direct administration. HPLC results showed that 1 mg of HLJD freeze-dried powder contained approximately 24 μg of geniposide， 15 μg of baicalin， and 30 μg of berberine. Based on these ratios， experimental groups were blank， LPS （2 mg·L^-1）， HLJD （200 mg·L^-1）， monomer combination， geniposide （4.8 mg·L^-1）， baicalin （3 mg·L^-1）， and berberine （6 mg·L^-1）. The monomer combination group consisted of all three active constituents dissolved together. LPS and HLJD or its active constituents did not affect cell viability compared with the blank group. LPS significantly increased TNF-α， IL-1β， IL-6， and IL-10 in the supernatant （P<0.01）. HLJD and its active constituents significantly reduced pro-inflammatory factors TNF-α， IL-1β， and IL-6 （P<0.05， P<0.01） while upregulating anti-inflammatory IL-10 （P<0.01）， with the monomer combination showing the strongest effect （P<0.05， P<0.01）. Compared with the blank group， LPS significantly increased the proportion of CD80⁺CD86⁺ （M1-type） BV2 cells （P<0.01）. HLJD and its constituents partially inhibited M1 polarization （P<0.05， P<0.01）， with the monomer combination exhibiting the most pronounced effect （P<0.05， P<0.01）. Compared with the blank group， LPS upregulated HMGB1， TLR4， and NF-κB-related proteins （P<0.01）， whereas HLJD and its active constituents significantly reduced their expression （P<0.05， P<0.01）， with the monomer combination having the strongest regulatory effect （P<0.05， P<0.01）. ConclusionHLJD and its major active constituents （geniposide， baicalin， berberine） can inhibit LPS-induced inflammatory responses in BV2 cells. The combination of the three active constituents demonstrates the most potent anti-inflammatory effect， significantly attenuating M1-type polarization of BV2 cells via the HMGB1/TLR4/NF-κB signaling pathway.

ObjectiveTo investigate the regulatory effects of Huanglian Jiedutang （HLJDT） on immune cell migration， blood-brain barrier protection， and cellular functional recovery in a model of ischemic stroke. MethodsA transient middle cerebral artery occlusion （tMCAO） model was established in mice to induce ischemic stroke. Cerebral blood flow and neurological function were evaluated using laser speckle imaging and neurological deficit scoring. Histopathological damage in brain tissues was assessed by hematoxylin-eosin （HE） and Nissl staining. Mice were divided into a sham group， a model group， an HLJDT group， and a Ginkgo biloba extract （GBE） group. After one week of acclimatization， intragastric administration was initiated. The sham and model groups received normal saline， the HLJDT group received HLJDT at 1.82 g·kg^-¹， and the GBE group received GBE at 0.432 g·kg^-¹. Administration was continued for 5 consecutive days， and the tMCAO model was established after the final dose on day 6. Single-cell RNA sequencing was performed on brain tissues and peripheral immune cells. UMAP and odds ratio （OR） indices were used to analyze cell distribution. Differential expression analysis was conducted to evaluate the effects of HLJDT on endothelial cells， pericytes， and macrophages， combined with CellChat and decoupler to analyze cell-cell communication and transcription factor regulation. Finally， PCR and ELISA were used to validate the mRNA and protein expression of relevant genes. ResultsCompared with the sham group， the model group showed significantly increased neurological deficit scores （P<0.01） and significantly decreased cerebral blood flow （P<0.01）， accompanied by cortical structural disorder， aggravated cytoplasmic vacuolization， and increased numbers of Nissl bodies. Compared with the model group， both the HLJDT and GBE groups exhibited significantly reduced neurological deficit scores （P<0.01） and markedly improved cerebral blood flow （P<0.01）， along with amelioration of cortical structural disorder， alleviated cytoplasmic vacuolization， and reduced numbers of Nissl bodies. Single-cell analysis showed that HLJDT protected endothelial cells and pericytes by preventing their reduction， restored the expression of functional genes in these cells （e.g.， PECAM1 and NOS3）， and downregulated the expression of chemokines and adhesion-related factors （e.g.， CCL2 and CXCL2）. In macrophages， HLJDT reduced their recruitment to the central nervous system and downregulated the expression of chemokine receptors and inflammatory factors （e.g.， IL-6， CCR2， and CXCR2）. Cell-cell communication analysis further indicated that HLJDT， through the above mechanisms， alleviated damage to pericytes and endothelial cells， reduced their recruitment of macrophages， and decreased ligand-receptor interactions in chemokine signaling pathways （including CCL， CXCL， and CSF3） between pericytes/endothelial cells and macrophages， thereby preventing secondary injury. Compared with the sham group， the model group showed significantly upregulated mRNA expression levels of IL-1β， IL-6， TNF-α， CCL2， CXCL2， and CSF3 （P<0.01）， while mRNA expression levels of endothelial- and pericyte function-related genes （RGS5， PECAM1， VEGFB， and NOS3） were significantly downregulated （P<0.01）. In contrast， compared with the model group， the HLJDT and GBE groups exhibited significantly decreased mRNA expression levels of IL-1β， IL-6， TNF-α， CCL2， CXCL2， and CSF3 （P<0.01）， and significantly increased expression of RGS5， PECAM1， VEGFB， and NOS3 （P<0.01）. At the protein level， compared with the sham group， the model group showed significantly increased expression of IL-1β， IL-6， and TNF-α （P<0.01）， whereas these protein levels were significantly reduced in the HLJDT and GBE groups compared with the model group （P<0.01）. ConclusionHLJDT reduces neuronal damage in ischemic stroke by protecting endothelial cells and pericytes， while inhibiting their interaction with macrophages， thereby mitigating secondary injury in the central nervous system.

Alzheimer’s disease (AD) is a central neurodegenerative disease characterized by progressive cognitive decline and memory impairment in clinical. Currently, there are no effective treatments for AD. In recent years, a variety of therapeutic approaches from different perspectives have been explored to treat AD. Although the drug therapies targeted at the clearance of amyloid β-protein (Aβ) had made a breakthrough in clinical trials, there were associated with adverse events. Neuroinflammation plays a crucial role in the onset and progression of AD. Continuous neuroinflammatory was considered to be the third major pathological feature of AD, which could promote the formation of extracellular amyloid plaques and intracellular neurofibrillary tangles. At the same time, these toxic substances could accelerate the development of neuroinflammation, form a vicious cycle, and exacerbate disease progression. Reducing neuroinflammation could break the feedback loop pattern between neuroinflammation, Aβ plaque deposition and Tau tangles, which might be an effective therapeutic strategy for treating AD. Traditional Chinese herbs such as Polygonum multiflorum and Curcuma were utilized in the treatment of AD due to their ability to mitigate neuroinflammation. Non-steroidal anti-inflammatory drugs such as ibuprofen and indomethacin had been shown to reduce the level of inflammasomes in the body, and taking these drugs was associated with a low incidence of AD. Biosynthetic nanomaterials loaded with oxytocin were demonstrated to have the capability to anti-inflammatory and penetrate the blood-brain barrier effectively, and they played an anti-inflammatory role via sustained-releasing oxytocin in the brain. Transplantation of mesenchymal stem cells could reduce neuroinflammation and inhibit the activation of microglia. The secretion of mesenchymal stem cells could not only improve neuroinflammation, but also exert a multi-target comprehensive therapeutic effect, making it potentially more suitable for the treatment of AD. Enhancing the level of TREM2 in microglial cells using gene editing technologies, or application of TREM2 antibodies such as Ab-T1, hT2AB could improve microglial cell function and reduce the level of neuroinflammation, which might be a potential treatment for AD. Probiotic therapy, fecal flora transplantation, antibiotic therapy, and dietary intervention could reshape the composition of the gut microbiota and alleviate neuroinflammation through the gut-brain axis. However, the drugs of sodium oligomannose remain controversial. Both exercise intervention and electromagnetic intervention had the potential to attenuate neuroinflammation, thereby delaying AD process. This article focuses on the role of drug therapy, gene therapy, stem cell therapy, gut microbiota therapy, exercise intervention, and brain stimulation in improving neuroinflammation in recent years, aiming to provide a novel insight for the treatment of AD by intervening neuroinflammation in the future.

Coronary chronic total occlusion(CTO)remains a significant challenge in the field of interventional therapy for coronary artery disease.With advancements in interventional techniques,particularly retrograde approaches,the success rate of CTO interventions has improved.The key steps of retrograde intervention include traversing collateral channels with the retrograde guidewire,wiring the occlusion segment,and establishing antegrade access.In this case,the patient had a heavily calcified occlusion at the left circumflex artery(LCX)ostium jailed by the prior stent implanted in the left main and anterior descending arteries,making it difficult to establish antegrade access using conventional methods after retrograde guidewire crossing.The procedure was successfully completed by employing a domestically developed intravascular snare system combined with a pre-assembled extension catheter technique to capture the retrograde guidewire and establish antegrade access,followed by stent implantation at the LCX ostium.This innovative approach provides a new strategy for complex CTO retrograde interventions,particularly in cases where retrograde guidewire entry into the antegrade guiding catheter is challenging.

Objective:To compare the efficacy and safety of a domestic hair follicle extraction system versus traditional follicular unit excision (FUE) in extracting hair follicles for the treatment of androgenetic alopecia (AGA) .Methods:A multicenter, randomized, self-controlled clinical trial was conducted on AGA patients aged 18 - 59 years who were recruited from the Huashan Hospital, Fudan University, the Affiliated Hangzhou First People's Hospital, and the China-Japan Friendship Hospital between June 2023 and September 2024. Each patient's scalp was randomly divided into two sides (experimental side vs. control side) using an envelope method. The experimental side underwent robotic hair transplantation with a domestic hair follicle extraction system, and the control side underwent traditional FUE. Hair follicles were extracted from the safe donor area in the occipital region, and implanted into the ipsilateral hair loss area. The primary outcome was the hair transection rate which was calculated immediately after follicular extraction. The secondary outcomes included the hair follicle unit loss rate and the change in hair density at the recipient site on postoperative day 14. Safety was evaluated by assessing the incidence of folliculitis at the donor site on postoperative day 14 and the overall incidence of adverse events. Surgical outcomes were evaluated at 9 months after surgery. Comparisons of evaluation indicators among groups were performed by using a paired t test or Wilcoxon signed-rank test. Results:A total of 55 patients with AGA (51 males and 4 females, aged 32.71 ± 5.75 years) completed the hair follicle transplantation and postoperative follow-up. The hair transection rate ( M[ Q1, Q3]) was 6.65% (4.56%, 10.16%) in the experimental group and 5.28% (3.04%, 8.89%) in the control group (difference = 1.24%, 95% CI: -0.24%, 2.65%) . The hair follicle unit loss rate was 2.00% (1.00%, 3.50%) in the experimental group and 0.50% (0, 2.00%) in the control group, with a significant difference between the two groups ( P = 0.008) . On postoperative day 14, there was no significant difference in the hair density between the experimental group and control group (72.20 ± 25.95 per cm 2vs. 76.49 ± 30.84 per cm 2, P = 0.173) . At 9-month follow-up, both groups showed improvement in the investigator's overall score in the recipient areas. Seven adverse events occurred in 7 subjects (12.72%) in each group, and all were mild folliculitis. Conclusion:The domestic hair follicle extraction system demonstrated comparable efficacy and safety to the traditional FUE in hair transplantation.

Objective:To compare the effects of propofol and dexmedetomidine for sedation on the outcome in mechanically ventilated patients with severe pulmonary infection.Methods:Patients with severe pulmonary infection (Clinical Pulmonary Infection Score >7) requiring mechanical ventilation from the Medical Information Mart for Intensive Care Ⅳ database between 2008 and 2020 were selected and divided into propofol group and dexmedetomidine group based on the sedative agent used. The primary outcome was all-cause in-hospital mortality, and secondary outcomes included 90-day all-cause mortality and duration of mechanical ventilation. Inverse probability of treatment weighting (IPTW) was used to adjust for baseline confounders, and logistic regression and linear regression were applied to analyze the effects of the two sedative drugs on the outcomes of mechanically ventilated patients with pulmonary infection. Kaplan-Meier survival curves were used to analyze survival outcomes.Results:A total of 6 204 critically ill patients with pulmonary infection requiring mechanical ventilation were included, with 3 439 cases in propofol group and 2 765 cases in dexmedetomidine group. The baseline characteristics between the two groups were well balanced (standardized mean difference < 0.1) after IPTW adjustment. In the IPTW-adjusted cohort, the in-hospital all-cause mortality and 90-day all-cause mortality were significantly lower in dexmedetomidine group than in propofol group (439.2[18.7%] vs 563.6[24.1%], 618.0[26.3%] vs 733.6[31.3%], P<0.001), the results of Further Kaplan-Meier survival curve analysis showed that the 90-day all-cause mortality was significantly lower in dexmedetomidine group than in propofol group ( P<0.01). Conclusions:Compared with propofol, dexmedetomidine can decrease the mortality rate and improve the prognosis in mechanically ventilated patients with severe pulmonary infection when used for sedation.