Chronic diabetic wounds, severely complicated by multidrug-resistant (MDR) bacterial infections, represent a profound and escalating global health crisis. The intrinsically hostile microenvironment of diabetic wounds, characterized by localized hypoxia, persistent oxidative stress, and poor vascularization, creates an ideal niche for opportunistic pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. These bacteria readily construct dense extracellular polymeric substance (EPS) biofilms, which not only physically shield the microbes from host immune responses but also actively trap the wound in a state of chronic, unresolved inflammation. Consequently, conventional systemic and topical antibiotic therapies are becoming increasingly futile, as poor perfusion at the wound site restricts drug bioavailability, while the rapid genetic evolution of bacteria and the impenetrable nature of biofilms lead to catastrophic treatment failures, often culminating in severe tissue necrosis and lower-extremity amputations. To circumvent the limitations of traditional antimicrobials, therapeutic gas delivery has emerged as a highly promising, paradigm-shifting strategy. Gaseous signaling molecules, particularly nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H₂S), and hydrogen (H₂), possess unique physicochemical properties that allow them to seamlessly penetrate dense biofilm matrices and cellular membranes. Once inside, these gases operate via multi-targeted mechanisms that are incredibly difficult for bacteria to develop resistance against; for instance, NO induces severe lipid peroxidation and DNA cleavage in bacteria, CO downregulates pro-inflammatory cytokines, H₂S significantly accelerates endothelial cell migration for neovascularization, and H₂ acts as a powerful selective antioxidant to neutralize tissue-damaging reactive oxygen species (ROS). Together, these therapeutic gases not only exert broad-spectrum bactericidal effects but also actively reprogram the wound bed by promoting the critical M1-to-M2 macrophage polarization and stimulating angiogenesis. Despite their immense biological potential, the direct clinical translation of gas therapies is severely hindered by inherent physicochemical drawbacks, including extreme volatility, short physiological half-lives, poor aqueous solubility, and the high risk of off-target systemic toxicity, if applied indiscriminately. To conquer these immense pharmacokinetic barriers, cutting-edge advancements in materials science have driven the development of gas-releasing micro- and nanoplatforms. Utilizing sophisticated carriers such as metal-organic frameworks (MOFs), mesoporous silica, polymeric nanoparticles, liposomes, and injectable hydrogels, researchers can now encapsulate gas-donor molecules to achieve sustained, localized delivery. More importantly, these advanced nanoplatforms are ingeniously engineered to be stimuli-responsive. By exploiting the pathological hallmarks of the diabetic wound environment, such as elevated glucose concentrations, acidic pH, and overexpressed ROS, or by utilizing external triggers like near-infrared (NIR) light irradiation and ultrasound, these intelligent platforms ensure on-demand, precise spatio-temporal gas release. This often allows for powerful synergistic combinations, such as photothermal or photodynamic therapy coupled with gas release, thereby obliterating biofilms while sparing healthy tissue. While the therapeutic outcomes of these smart delivery systems in eradicating MDR infections and accelerating tissue repair are unprecedented, several critical challenges remain before widespread clinical adoption, as long-term biosafety profiles of the carrier nanomaterials, complexities in large-scale good manufacturing practice (GMP) production, and stringent regulatory hurdles must be rigorously addressed. Looking forward, the next frontier lies in the realm of precision medicine and theranostics, where future research must focus on the seamless integration of these gas-releasing platforms with flexible, wearable biosensors capable of continuously monitoring wound biomarkers (e.g., pH, temperature, uric acid) in real-time. Coupled with artificial intelligence algorithms to govern automated, closed-loop adaptive dosing, these next-generation smart dressings hold the ultimate potential to comprehensively transform the clinical management of complex, infected diabetic wounds.

ObjectiveThe most prevalent mRNA modification, N6-methyladenosine (m⁶A) plays an important role in various RNA metabolism, including gene expression and translation. By recruiting different “reader” proteins and their cofactors, m⁶A modification can affect messenger RNA (mRNA) degradation, splicing, nuclear export and translation. However, the selective mechanism by which m⁶A sites regulate mRNA translation through m⁶A reader YTHDF1 binding remains poorly understood, due to a lack of computational methods for identifying context-specific m⁶A sites that regulate translation. To address this, we developed a novel computational framework named m⁶ATEpre, the first tool designed to predict cell-specific m⁶A sites that regulate translation efficiency. Methodsm⁶ATEpre integrates multi-omics data, introduces a novel feature representation strategy for m⁶A site sequences, and employs an autoencoder to effectively capture embedded feature representations. Specifically, m⁶ATEpre first integrated MeRIP-seq data and PAR-CLIP data through overlapping m⁶A sites with YTHDF1 binding sites and identified YTHDF1-mediated m⁶A sites. Then, m⁶ATEpre detected the translation gene by analyzing the Ribo-seq data under YTHDF1 knockdown vs control condition. Genes whose translation is mediated by YTHDF1 in an m⁶A-dependent manner were identified by a significant decrease in translation efficiency upon YTHDF1 knockdown. Next, we proposed a binary vector indicating the presence or absence of YTHDF1 binding motifs to characterize each m⁶A site sequence. This represents a novel feature representation strategy for m⁶A sites. m⁶ATEpre utilized the autoencoder to extract the potentially important feature representations and constructed a multilayer perceptron neural networks model to predict potential m⁶A sites that regulating translation efficiency. ResultsA comprehensive evaluation of m⁶ATEpre was conducted through a series of experiments. We compared its performance against that of a similar prediction task model, as well as other classifiers. The results indicate that m⁶ATEpre achieved the best prediction performance. In addition, we analyzed different feature representation strategies and performed ablation experiments to validate the rationality of the model design. The results demonstrate that our proposed feature representation strategy has a greater advantage in improving prediction performance. In the HeLa cell line, bioinformatic analysis of the metagene distribution and sequence minimum free energy of m⁶A sites regulating translation efficiency (m⁶A-reg-TE sites) revealed their specific properties in translation regulation. Functional enrichment analysis indicated that m⁶A-reg-TE genes are associated with specific biological processes and KEGG pathways. By integrating the binding sites of YTHDF1 co-factors with m⁶A-reg-TE sites, we revealed that YTHDF1-mediated and m⁶A-dependent translation efficiency regulation requires the cooperation of multiple translation-regulatory RNA-binding proteins among its co-factors in the HeLa cell line. Furthermore, we extended our predictions to the dataset of the HEK293T cell line. Similarly, bioinformatic analysis of the metagene distribution and functional enrichment revealed the cell-specific characteristic of these predicted m⁶A-reg-TE sites in HEK293T cells. Likewise, integrated analysis of multiple YTHDF1 co-factors and m⁶A-reg-TE sites predicted in the HEK293T cell line reveals their m⁶A-dependent cooperation in regulating translation efficiency. Conclusionm⁶ATEpre is a timely tool that will advance our understanding of the mechanisms of m⁶A regulation in translation efficiency. The source code and datasets used in this work can be downloaded from https://www.scidb.cn/s/bAZZFr.

OBJECTIVE: To summarize the clinical features and management of two brothers affected with X-linked inhibitor of apoptosis protein (XIAP) deficiency. METHODS: This study retrospectively analyzed the clinical presentations, treatment, and follow-up of two brothers with XIAP deficiency diagnosed at Shanghai Children's Hospital in 2020, and summarized similar cases recorded in databases such as PubMed, Wanfang, Chinese Medical Association Journals, and WIP from January 2006 to November 2024. This study was approved by the Medical Ethics Committee of our hospital (Ethics No.: 2025R128-E01). RESULTS: Patient 1 was the younger brother, who presented at 8 years of age with growth retardation, folliculitis, erythema nodosum, and perineal abscess. Sequencing revealed that he has carried a hemizygous c.566T>C (p.Leu189Pro) variant of the XIAP gene, which was inherited from his mother. He was allergic to infliximab treatment and underwent allogeneic stem cell transplantation (HSCT) in January 2021. During a follow-up of 3 years and 10 months post-transplantation, he showed no gastrointestinal symptoms and had a good outcome. Patient 2 was the elder brother, who presented at 10 years and 6 months of age with growth retardation, rash, and anal fistula. Genetic testing revealed the same variant. He was treated with oral azathioprine but did not have regular follow-ups. At 14-years-and-6-months of age, he had developed severe gastrointestinal infection and hemophagocytic lymphohistiocytosis, which was alleviated after treatment with antibiotics, glucocorticoids, immunoglobulin, and rituximab. He is currently being prepared for HSCT. A total of 13 publications were retrieved, which involved 64 patients from 23 families, with 23 different variants identified. The main clinical manifestations included splenomegaly (34 cases, 53.1%), hemophagocytic lymphohistiocytosis (27 cases, 42.2%), and inflammatory bowel disease or colitis (20 cases, 31.8%). There were significant phenotypic differences among patients from the same family. Thirteen patients (20.3%) underwent HSCT, with a survival rate of 61.5%. CONCLUSION For male children with early onset, poor treatment response, especially those with unexplained splenomegaly and IBD-like symptoms, early genetic testing is recommended. HSCT is a safe and effective treatment for XIAP deficiency. For patients with developmental delay, early onset, and severe IBD phenotype, early transplantation is recommended.
Humans ; Male ; X-Linked Inhibitor of Apoptosis Protein/deficiency* ; Child ; Genetic Diseases, X-Linked/therapy* ; Phenotype ; Siblings ; Retrospective Studies ; Hematopoietic Stem Cell Transplantation

Huanglian Jiedutang （HLJDT）， as a classical formula for clearing heat and removing toxins， has been widely applied in the treatment of various clinical diseases in recent years， particularly during the fire-heat stage of stroke， where it has attracted considerable attention. Based on previous studies， this paper systematically elaborates on the research progress on the active components of HLJDT， its clinical application in ischemic stroke， and advances in studies on its mechanisms of action. Modern pharmacological studies have demonstrated that HLJDT contains multiple active components， including baicalin， geniposide， and berberine. In the treatment of ischemic stroke， these components exert therapeutic effects through multi-target， multi-pathway， and multi-level mechanisms. Clinical studies have shown that HLJDT can increase cerebral blood flow， reduce cerebral infarct volume， and improve post-stroke physical dysfunction in patients with ischemic stroke. Experimental studies have indicated that HLJDT can improve neurological function scores and increase cerebral perfusion in experimental stroke models. In addition， the mechanisms underlying the anti-ischemic stroke effects of HLJDT may be related to anti-inflammatory and antioxidant activities， promotion of angiogenesis， and regulation of amino acid and energy metabolism. Although existing studies have confirmed that HLJDT exhibits multi-target and multi-pathway synergistic therapeutic characteristics， further large-sample randomized controlled trials are still needed to verify its long-term efficacy and to further elucidate the dynamic interaction network among components， targets， and pathways. Combined with network pharmacology and molecular docking analyses， this study further clarifies the synergistic targets of the core components （berberine， baicalin， and geniposide）， providing a theoretical basis for in-depth research and clinical translation of HLJDT in the treatment of ischemic stroke.

ObjectiveTo observe the clinical efficacy and radiographic outcomes of manipulative reduction combined with small splint fixation in the treatment of distal radius fractures. MethodsThe clinical data of 1051 patients with distal radius fractures were retrospectively collected from five hospitals included in the Jiangsu Diagnosis and Treatment Data Platform for Traditional Chinese Medicine（TCM） Dominant Diseases. Propensity score matching at a 1∶4 ratio was applied， resulting in 580 cases selected for final analysis， which comprised 448 patients in the TCM group（manipulative reduction plus small splint fixation） and 132 in the surgical treatment group（open reduction and internal fixation）. Each group was further stratified into type A， B， and C subgroups based on AO fracture classification. Radiographic indicators including palmar tilt， radial inclination， and radial height were compared between groups before treatment and 1 day， 1 week， and 4-6 weeks after treatment， and pain visual analog scale（VAS） scores before treatment and 1 week and 4-6 weeks after treatment were also compared. Wrist joint function was assessed 12 weeks after treatment， using the Dienst wrist function score and the Gartland and Werley（G-W） wrist function score. Additionally， the radiographic indicators at different timepoints and the 12-week wrist function levels were compared between groups across different fracture types. ResultsNo statistically significant difference was observed in radiographic indicators and VAS scores at all timepoints before and after treatment， as well as wrist joint function grades assessed by the Dienst score and the G-W score at 12 weeks after treatment （P＞0.05）. Compared to those before treatment， both groups showed increased palmar tilt， radial inclination， and radial height 1 week and 4-6 weeks after treatment， and decreased VAS scores （P＜0.05）. Compared to those 1 week after treatment， both groups showed a decrease in palmar tilt， an increase in radial inclination and radial height， and a reduction in VAS score 4-6 weeks after treatment（P＜0.05）. In type A and B subgroups， the surgical treatment group had a higher radial inclination than the TCM group 4-6 weeks after treatment， while in the type C subgroup， a higher radial height was shown in the surgical treatment group than in the TCM group 4-6 weeks after treatment（P＜0.05）. In type C subgroup， there was significant difference between groups in the wrist joint function by G-W scores 12 weeks after treatment（P＜0.05）. ConclusionManipulative reduction combined with small splint fixation can maintain fracture alignment and alleviate pain in treating distal radius fractures， which achieves therapeutic outcomes comparable to surgical treatment. It is particularly suitable for type A and B fractures and can be considered an effective treatment option for distal radius fractures.

Chronic diabetic wounds, severely complicated by multidrug-resistant (MDR) bacterial infections, represent a profound and escalating global health crisis. The intrinsically hostile microenvironment of diabetic wounds, characterized by localized hypoxia, persistent oxidative stress, and poor vascularization, creates an ideal niche for opportunistic pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. These bacteria readily construct dense extracellular polymeric substance (EPS) biofilms, which not only physically shield the microbes from host immune responses but also actively trap the wound in a state of chronic, unresolved inflammation. Consequently, conventional systemic and topical antibiotic therapies are becoming increasingly futile, as poor perfusion at the wound site restricts drug bioavailability, while the rapid genetic evolution of bacteria and the impenetrable nature of biofilms lead to catastrophic treatment failures, often culminating in severe tissue necrosis and lower-extremity amputations. To circumvent the limitations of traditional antimicrobials, therapeutic gas delivery has emerged as a highly promising, paradigm-shifting strategy. Gaseous signaling molecules, particularly nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H₂S), and hydrogen (H₂), possess unique physicochemical properties that allow them to seamlessly penetrate dense biofilm matrices and cellular membranes. Once inside, these gases operate via multi-targeted mechanisms that are incredibly difficult for bacteria to develop resistance against; for instance, NO induces severe lipid peroxidation and DNA cleavage in bacteria, CO downregulates pro-inflammatory cytokines, H₂S significantly accelerates endothelial cell migration for neovascularization, and H₂ acts as a powerful selective antioxidant to neutralize tissue-damaging reactive oxygen species (ROS). Together, these therapeutic gases not only exert broad-spectrum bactericidal effects but also actively reprogram the wound bed by promoting the critical M1-to-M2 macrophage polarization and stimulating angiogenesis. Despite their immense biological potential, the direct clinical translation of gas therapies is severely hindered by inherent physicochemical drawbacks, including extreme volatility, short physiological half-lives, poor aqueous solubility, and the high risk of off-target systemic toxicity, if applied indiscriminately. To conquer these immense pharmacokinetic barriers, cutting-edge advancements in materials science have driven the development of gas-releasing micro- and nanoplatforms. Utilizing sophisticated carriers such as metal-organic frameworks (MOFs), mesoporous silica, polymeric nanoparticles, liposomes, and injectable hydrogels, researchers can now encapsulate gas-donor molecules to achieve sustained, localized delivery. More importantly, these advanced nanoplatforms are ingeniously engineered to be stimuli-responsive. By exploiting the pathological hallmarks of the diabetic wound environment, such as elevated glucose concentrations, acidic pH, and overexpressed ROS, or by utilizing external triggers like near-infrared (NIR) light irradiation and ultrasound, these intelligent platforms ensure on-demand, precise spatio-temporal gas release. This often allows for powerful synergistic combinations, such as photothermal or photodynamic therapy coupled with gas release, thereby obliterating biofilms while sparing healthy tissue. While the therapeutic outcomes of these smart delivery systems in eradicating MDR infections and accelerating tissue repair are unprecedented, several critical challenges remain before widespread clinical adoption, as long-term biosafety profiles of the carrier nanomaterials, complexities in large-scale good manufacturing practice (GMP) production, and stringent regulatory hurdles must be rigorously addressed. Looking forward, the next frontier lies in the realm of precision medicine and theranostics, where future research must focus on the seamless integration of these gas-releasing platforms with flexible, wearable biosensors capable of continuously monitoring wound biomarkers (e.g., pH, temperature, uric acid) in real-time. Coupled with artificial intelligence algorithms to govern automated, closed-loop adaptive dosing, these next-generation smart dressings hold the ultimate potential to comprehensively transform the clinical management of complex, infected diabetic wounds.

Objective:To investigate the current status of knowledge, attitude, and practice (KAP) of intensive care unit (ICU) medical staff for post-intensive care syndrome (PICS) and explore its influencing factors.Methods:The cross-sectional investigation study with stratified sampling was conducted. From June to September 2024, ICU medical staff from general hospitals in 5 regions (Chongqing, Beijing, Shaanxi, Jiangsu, and Gansu) were selected as the research subjects. The KAP of PICS questionnaire was distributed in the form of an electronic questionnaire. Observation indicators: (1) results of the questionnaire survey; (2) general information of ICU medical staff; (3) KAP scores of PICS and the correlation among various dimensions; (4) analysis of influencing factors for KAP of PICS. Comparison of measurement data with normal distribution between groups was conducted using the independent samples t test. One-way analysis of variance (ANOVA) was applied for com-parison among multiple groups, and post-hoc LSD test was used for pairwise comparison. Comparison of count data between groups was conducted using the chi-square test. Pearson correlation analysis was adopted for correlation analysis. Multiple linear regression analysis was used for univariate and multivariate analyses. Results:(1) Results of questionnaire survey. A total of 410 questionnaires were distributed and retrieved, among which 408 were valid, with an effective rate of 99.512%(408/410). (2) General information of ICU medical staff. Among the 408 ICU medical staff, there were 79 males and 329 females. Eight cases were under 25 years old, 248 cases were 25-35 years old, 132 cases were 36-40 years old, and 20 cases were over 40 years old. In terms of professional title, there were 10 junior nurses, 130 junior nurse practitioners, 228 intermediate nurse practitioners, and 40 senior nurse practitioners. About the educational background, 34 cases had a junior college degree, 347 cases had a bachelor's degree, and 27 cases had a master's degree or above. Regarding the hospital level, 25 nurses worked in secondary hospitals and 383 cases in tertiary hospitals. In terms of ICU type, 181 cases were from specialized ICU and 227 cases from general ICU. About working experience in ICU, 41 nurses had less than 5 years, 207 cases had 5-10 years, and 160 cases had more than 10 years. (3) KAP scores of PICS and the correlation among various dimensions. The total KAP score of PICS among the 408 ICU medical staff was 88.7±14.2, with 40.2±9.2 for the knowledge dimension, 22.0±5.6 for the attitude dimension, and 26.5±6.3 for the practice dimension. Pearson correlation analysis showed that the knowledge dimension of PICS among ICU medical staff was significantly positively correlated with both the attitude dimension and the practice dimension ( r=0.15, 0.69, P<0.05); the attitude dimension was positively correlated with the practice dimension ( r=0.23, P<0.05).(4) Analysis of influencing factors for KAP of PICS. Results of multivariate analysis showed that age (25-35 years old, 36-40 years old, over 40 years old), educational background and hospital level were independent influencing factors for the KAP of PICS among ICU medical staff ( t=2.23, 1.97, 2.84, 0.15, 2.04, P<0.05). Conclusions:The KAP of PICS among ICU medical staff is relatively good, while their practical ability still needs to be improved. Age, educational background, and hospital level are independent influencing factors for the KAP of PICS among ICU medical staff.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective:To identify risk factors associated with endoscopic atrophic progression of gastric mucosa after Helicobacter pylori ( HP) eradication and to develop a risk scoring system for establishing an individualized endoscopic follow-up strategy for patients with chronic gastritis. Methods:This retrospective cohort study included chronic gastritis patients with successful HP eradication at the Department of Gastroenterology, Beijing Friendship Hospital between January 2018 and October 2021. Demographic characteristics, endoscopic findings, and other clinical data were analyzed. Endoscopic outcomes of gastric mucosal atrophy before and after follow-up were compared to classify patients into progression and non-progression groups. Univariate and multivariate analyses were performed to identify independent risk factors for endoscopic atrophic progression. A risk scoring system was then constructed based on these factors. Results:A total of 218 patients with chronic gastritis were included, including 153 in the non-progression group and 65 in the progression group. Multivariate logistic regression analysis showed that gastric ulcer ( P=0.008, OR=4.24, 95% CI: 1.46-12.25), history of proton pump inhibitor use ( P=0.007, OR=4.06, 95% CI: 1.46-11.27), alcohol consumption ( P=0.002, OR=3.77, 95% CI: 1.64-8.67), high-salt diet ( P=0.008, OR=2.90, 95% CI: 1.32-6.41), and high red meat intake ( P=0.025, OR=2.33, 95% CI: 1.11-6.31) were independent risk factors for endoscopic atrophic progression after HP eradication. The predictive model based on these 5 factors demonstrated strong discriminative capacity, with an area under the receiver operating characteristic curve of 0.813 (95% CI: 0.755-0.876, P<0.001). The optimal cut-off value was 1.5 points, stratifying patients into low-risk (0-2 points) and high-risk (3-5 points) groups. Conclusion:Patients with chronic gastritis remain susceptible to progression even after successful HP eradication. Individualized endoscopic follow-up strategies should be considered based on patients' medical history, medication use, lifestyle, and dietary habits.

Lung cancer poses a serious threat to global public health security.Chemotherapy,as the main strategy for cancer treatment,faces challenges such as high toxicity and drug resistance.Anticancer peptides have the potential of being developed into new anticancer drugs due to their advantages of broad-spectrum anticancer activity,rapid action,and difficulty in generating drug resistance,but they also face shortcomings such as weak activity and strong toxic side effects.The weakly acidic microenvironment of tumors(pH 6.5-6.8)provides a good idea for the design of anticancer peptides of high-efficiency and low-toxicity.Previously,we designed the acid-sensitive antibacterial peptide pHly-1 using the wolf spider(Lycosa singoriensis)toxin Lycosin-Ⅰ as a template.In this study,we found that pHly-1 also had acid-sensitive anticancer activity.Further alanine scanning analysis of pHly-1 was carried out,and we ob-tained a mutant pHTP-2 with better acid sensitivity,whose IC50(half maximal inhibitory concentration)against A549 cells was 15.68 μmol/L at pH 6.6 and was greater than 100 μmol/L at pH 7.4.At pH 6.6,pHTP-2 could act on various lung cancer cell lines and induce the death of A549 cells by rapid ly-sis;at pH 7.4,500 μmol/L pHTP-2 had weak toxicity to red blood cells(the hemolysis rate was ap-proximately 38％)and primary myocardial cells(the inhibition rate was 49.7％,with P＜0.05).Analy-sis of its charge,particle size,morphology,and secondary structure showed that at pH 6.6,the histidine in the sequence of pHTP-2 was protonated,increasing the positive charge(P＜0.01),decreasing the hy-drated particle size(P＜0.05)and forming an α-helical structure to induce membrane lysis of A549 cells.At pH 7.4,it was deprotonated,the positive charge decreases,a β-sheet structure was formed and self-aggregation occurred,limiting its effect on the A549 cell membrane and showing weak activity.In summary,pHTP-2 could respond to the weakly acidic microenvironment of tumors to exert selective cyto-toxic activity,effectively overcoming the shortcomings of anticancer peptides such as low efficiency and high toxicity.Our findings suggest that it is a high-quality lead molecule for anticancer drugs.