AIM:To investigate the effects of high-altitude hypoxic exposure on retinal injury and the associated changes in oxidative stress-related indicators in rats. METHODS: Twenty-four healthy male Sprague-Dawley(SD)rats were randomly divided into a plain group and a high-altitude group, with 12 rats(24 eyes)in each group. Rats in the plain group were housed under normoxic conditions in an SPF-grade animal facility, whereas rats in the high-altitude group were placed in a special environmental chamber simulating an altitude of 6 000 m for 7 d. Optical coherence tomography(OCT)was used to assess retinal layer architecture and quantify retinal thickness. Hematoxylin-eosin(HE)staining was performed to observe retinal histopathological changes. Immunofluorescence(IF)was used to detect the expression of hypoxia-inducible factor-1α(HIF-1α)in retinal tissue. Transmission electron microscopy(TEM)was applied to examine the ultrastructure of retinal ganglion cells(RGCs). Enzyme-linked immunosorbent assay(ELISA)was used to measure the levels of malondialdehyde(MDA), total superoxide dismutase(T-SOD), and reduced glutathione(GSH)in retinal tissue. In addition, intracellular reactive oxygen species(ROS)levels in retinal tissue were assessed using the 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA)fluorescent probe. RESULTS: OCT examination revealed disorganized retinal architecture in the high-altitude group, with increased inner and middle ring thickness and decreased outer ring thickness compared with the plain group(all P<0.05). HE staining showed varying degrees of retinal layer damage, blurred layer boundaries, loosely arranged RGCs, and partial cellular necrosis in the high-altitude group. IF analysis demonstrated significantly increased HIF-1α expression in the inner nuclear layer of the high-altitude group(P<0.01). TEM revealed mitochondrial swelling, disrupted cristae, and reduced matrix electron density in RGCs of the high-altitude group. ELISA and fluorescence probe assays showed significantly elevated MDA levels and ROS fluorescence intensity, accompanied by decreased T-SOD and GSH levels in the retinal tissue of the high-altitude group(all P<0.05). CONCLUSION: Exposure to a high-altitude hypoxic environment induces marked morphological and ultrastructural damage in the rat retina and significantly enhances oxidative stress, suggesting that oxidative stress may play a critical role in retinal injury induced by high-altitude hypoxia.

ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.

ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.

Objective To investigate the influencing factors of antibiotic-associated diarrhea(AAD)following congenital heart disease(CHD)surgery in pediatric patients,develop a nomogram-based predictive model,and validate its efficacy.Methods A retrospective analysis was conducted on the clinical data of pediatric patients who underwent CHD surgery in the Pediatric Intensive Care Unit(PICU)of a tertiary hospital in Guang-dong Province from July 2022 to July 2024.Patients were categorized into an AAD group and a non-AAD group.Univariate and multivariate logistic regression analyses were performed to identify risk factors for AAD occurrence following CHD surgery.A risk prediction model was developed,and a nomogram was constructed.The predictive performance of the model was evaluated using the Receiver Operating Characteristic(ROC)curve to calculate the area under the curve(AUC),the Hosmer-Lemeshow goodness-of-fit test,calibration curves,and clinical decision curve analysis.External validation of the model was conducted using data from patients in the Surgical Intensive Care Unit(SICU).Results The incidence of AAD following CHD surgery was 48.52%(229 out of 472 cases).Risk factors for AAD included the combined use of antibiotics,mechanical ventilation,elevated C-reactive protein levels,prolonged surgical duration,and extended antibiotic usage time(all with OR>1,P<0.05).Conversely,probiotic administration was identified as a protective factor(OR<1,P<0.05).The predictive model demon-strated excellent discrimination,as evidenced by the ROC curve areas:0.922(95%CI:0.894～0.951)in the modeling group,0.886(95%CI:0.838～0.915)in the internal validation group,and 0.862(95%CI:0.784～0.941)in the external validation group.Additionally,the model exhibited satisfactory calibration,as indicated by the Hosmer-Lemeshow test results:χ2=7.96,P=0.538 in the modeling group;χ2=4.24,P=0.895 in the inter-nal validation group;and χ2=9.923,P=0.270 in the external validation group.Furthermore,the model provided significant clinical utility.Conclusions Combined antibiotic use,duration of antibiotic therapy,mechanical ventilation,surgical duration,C-reactive protein(CRP)levels,and probiotic administration are key factors influ-encing the occurrence of AAD.The risk prediction model developed based on these variables demonstrates robust predictive performance and can serve as a valuable reference for the development and implementation of preventive and therapeutic strategies in clinical practice.

Breast cancer is one of the most prevalent malignant tumor in women worldwide,in which,triple-negative breast cancer(TNBC)is highly invasive and metastatic.In recent years,the incidence rate of TNBC has gradually increased and shown a trend of younger age.With the in-depth research on the molecular mechanism of breast cancer,neuropilin-1(NRP-1),a transmembrane protein,has been found to be associated with metastasis and prognosis of breast cancer,particularly TNBC.Therefore,NRP-1 has become a promising target for the diagnosis and treatment of breast cancer.The expression and distribution of NRP-1 in breast cancer can be detected by nuclear medicine,optical imaging and multimodal imaging methods in a non-invasive,real-time and accurate manner,which has significant application value in the early diagnosis,staging,treatment,and prognosis evaluation of breast cancer.Nuclear medicine probes specifically target tumor cells or tissues by combining radionuclides(e.g.,68Ga and 99mTc)with specific molecular ligands,and the signal is captured using positron emission tomography(PET)or single-photon emission computed tomography(SPECT),allowing for sensitive diagnosis of breast cancer.With the development of medical imaging and other interdisciplinary subjects,the NRP-1 targeted multimodal molecular probe[68Ga]Ga-NODAGA-K(Cy5)DKPPR combined the high sensitivity of PET with the high resolution advantage of near-infrared fluorescence(NIRF)to achieve precise diagnosis of breast cancer and provide real-time fluorescence navigation during surgery,enhancing the accuracy of tumor tissue identification and excision.In this paper,the advantages and disadvantages of NRP-1 targeted molecular probes in the diagnosis of breast cancer were systematically compared,and the application scope and latest research progress of various probes in the diagnosis and treatment of breast cancer were described,in order to provide reference for the development and clinical application of breast cancer targeted molecular probes.

Objective To investigate the influencing factors of antibiotic-associated diarrhea(AAD)following congenital heart disease(CHD)surgery in pediatric patients,develop a nomogram-based predictive model,and validate its efficacy.Methods A retrospective analysis was conducted on the clinical data of pediatric patients who underwent CHD surgery in the Pediatric Intensive Care Unit(PICU)of a tertiary hospital in Guang-dong Province from July 2022 to July 2024.Patients were categorized into an AAD group and a non-AAD group.Univariate and multivariate logistic regression analyses were performed to identify risk factors for AAD occurrence following CHD surgery.A risk prediction model was developed,and a nomogram was constructed.The predictive performance of the model was evaluated using the Receiver Operating Characteristic(ROC)curve to calculate the area under the curve(AUC),the Hosmer-Lemeshow goodness-of-fit test,calibration curves,and clinical decision curve analysis.External validation of the model was conducted using data from patients in the Surgical Intensive Care Unit(SICU).Results The incidence of AAD following CHD surgery was 48.52%(229 out of 472 cases).Risk factors for AAD included the combined use of antibiotics,mechanical ventilation,elevated C-reactive protein levels,prolonged surgical duration,and extended antibiotic usage time(all with OR>1,P<0.05).Conversely,probiotic administration was identified as a protective factor(OR<1,P<0.05).The predictive model demon-strated excellent discrimination,as evidenced by the ROC curve areas:0.922(95%CI:0.894～0.951)in the modeling group,0.886(95%CI:0.838～0.915)in the internal validation group,and 0.862(95%CI:0.784～0.941)in the external validation group.Additionally,the model exhibited satisfactory calibration,as indicated by the Hosmer-Lemeshow test results:χ2=7.96,P=0.538 in the modeling group;χ2=4.24,P=0.895 in the inter-nal validation group;and χ2=9.923,P=0.270 in the external validation group.Furthermore,the model provided significant clinical utility.Conclusions Combined antibiotic use,duration of antibiotic therapy,mechanical ventilation,surgical duration,C-reactive protein(CRP)levels,and probiotic administration are key factors influ-encing the occurrence of AAD.The risk prediction model developed based on these variables demonstrates robust predictive performance and can serve as a valuable reference for the development and implementation of preventive and therapeutic strategies in clinical practice.

Breast cancer is one of the most prevalent malignant tumor in women worldwide,in which,triple-negative breast cancer(TNBC)is highly invasive and metastatic.In recent years,the incidence rate of TNBC has gradually increased and shown a trend of younger age.With the in-depth research on the molecular mechanism of breast cancer,neuropilin-1(NRP-1),a transmembrane protein,has been found to be associated with metastasis and prognosis of breast cancer,particularly TNBC.Therefore,NRP-1 has become a promising target for the diagnosis and treatment of breast cancer.The expression and distribution of NRP-1 in breast cancer can be detected by nuclear medicine,optical imaging and multimodal imaging methods in a non-invasive,real-time and accurate manner,which has significant application value in the early diagnosis,staging,treatment,and prognosis evaluation of breast cancer.Nuclear medicine probes specifically target tumor cells or tissues by combining radionuclides(e.g.,68Ga and 99mTc)with specific molecular ligands,and the signal is captured using positron emission tomography(PET)or single-photon emission computed tomography(SPECT),allowing for sensitive diagnosis of breast cancer.With the development of medical imaging and other interdisciplinary subjects,the NRP-1 targeted multimodal molecular probe[68Ga]Ga-NODAGA-K(Cy5)DKPPR combined the high sensitivity of PET with the high resolution advantage of near-infrared fluorescence(NIRF)to achieve precise diagnosis of breast cancer and provide real-time fluorescence navigation during surgery,enhancing the accuracy of tumor tissue identification and excision.In this paper,the advantages and disadvantages of NRP-1 targeted molecular probes in the diagnosis of breast cancer were systematically compared,and the application scope and latest research progress of various probes in the diagnosis and treatment of breast cancer were described,in order to provide reference for the development and clinical application of breast cancer targeted molecular probes.

OBJECTIVE: To explore the functional rehabilitation of patients with rheumatoid arthritis (RA) after total knee arthroplasty (TKA). METHODS: A retrospective analysis was conducted on 101 patients who needed TKA due to rheumatoid arthritis (RA) involving both knees from January 2017 to December 2020, including 16 males and 85 females, aged from 41 to 65 years old with an average of (58.13±5.53) years old;body mass index (BMI) ranged from 16.88 to 33.33 kg·m^-2 with an average of (23.16±3.49) kg·m^-2;63 patients with grade 1, 29 patients with grade 2, and 9 patients with grade 3 according to classification of American Society of Anesthesiologists (ASA). According to the latest follow-up results at 12 months after operation, 82 patients returned to work and 19 patients did not return to work. Visual analogue scale(VAS) was used to evaluate the degree of pain relief before operation and 12 months after operation, and work, osteoarthritis and joint replacement questionnaire (WORQ) was used to evaluate knee joint activity status of all patients before and after operation, and the working ability index was used to evaluate working ability of all patients before operation and 12 months after operation. For the 82 patients who returned to work, the labor time stopped before operation and within 12 months after operation was compared, and the changes in labor grades, types of work and labor hours of patients before and after operation were recorded. For the 19 patients who did not return to work, the specific reasons for their non-return to work was analyzed;the postoperative satisfaction of patients was evaluated by using Likert satisfaction scale. All patients were followed up for at least 12 months. VAS was decreased from (6.49±0.59) before operation to (1.10±0.43) at 12 months after operation (P<0.05);for WORQ questionnaire survey, scores of walking, sitting posture, standing and stair climbing were increased from (1.07±0.35), (1.05±0.29), (1.06±0.34) and (1.14±0.42) before operation to (3.00±0.00), (2.87±0.33), (2.95±0.21) and (2.95±0.21) after operation, respectively, had statistically significant (P<0.05);the labor work index of all patients increased from 1.11±0.46 before operation to 2.99±0.10 at 12 months after operation, and the difference was statistically significant (P<0.05). Among the 82 patients who returned to work after operation, regarding the time of stopping labor, 81 patients stopped working within 3 months before operation, 1 patient stopped working for 4 to 6 months after operation, and the number of patients who stopped working was 81, 1, and 0 respectively. Forty patients returned to work within 3 months after operation, 4 to 6 months after operation for 29 patients, and 12 months after operation for 13 patients. 95.1% (78/82) of patients engaged in light labor before operation, and 85.4% (70/82) of patients engaged in moderate labor after operation. At 12 months after operation, the types of jobs and working hours available to all patients increased compared with those before operation. Among 19 patients who did not return to work after TKA, 7 patients had poor control of rheumatoid arthritis, 5 patients still felt pain, swelling and numbness on knee joint, 2 patients had retired, and 5 patients had other reasons. Eighty-six patients (85%) expressed great satisfaction with the postoperative working ability, 8 patients (8%) expressed satisfaction with the postoperative working ability, 6 patients (6%) expressed acceptance of postoperative working ability, and 1 patient (1%) expressed dissatisfaction with postoperative working ability. CONCLUSION TKA is an effective treatment option for patients with RA. After undergoing TKA, patients could significantly improve pain and functional activities of knee joint, and effectively enhance the quality of life and working ability. For patients whose rehabilitation labor capacity is not fully met, postoperative management and personalized rehabilitation treatment need to be strengthened to achieve the best rehabilitation effect.
Humans ; Female ; Male ; Arthroplasty, Replacement, Knee/rehabilitation* ; Arthritis, Rheumatoid/physiopathology* ; Middle Aged ; Aged ; Retrospective Studies ; Adult

Objective:To investigate the current status and challenges of pediatric life support training in China and provide references for improving training quality.Methods:A cross-sectional study was conducted to collect data from pediatric life support training centers across the country，covering basic institutional information，training capacity and training faculty，training program funding，as well as existing challenges and issues.The domestic registry of training centers in 2023 was obtained through the American Heart Association's online platform.After contacting and verifying each center，an online questionnaire was distributed，and the aggregated data were statistically analyzed.Results:A total of 42 institutions participated in the survey，including 19 children's hospitals，14 general hospitals，6 maternal and child health hospitals，2 women and children’s hospitals，and 1 training institution.The distribution of training centers showed a concentration in coastal areas，with the top three provinces/municipalities being Guangdong（7/42，16.7%），Zhejiang（6/42，14.3%），and Shanghai（4/42，9.5%）.As of December 31 2023，the 42 institutions had an annual basic life support（BLS）training volume of 8 587 individuals，the median was 120 (100,200)，and an annual pediatric advanced life support（PALS）training volume of 2 448 individuals，the median was 30 (20,50).Among the 42 institutions，there were 598 BLS instructors and 306 PALS instructors.Among the surveyed institutions，24（24/42，57.1%）reported BLS instructor teams comprising fewer than 10 members，and 33（33/42，78.6%）reported PALS instructor teams comprising fewer than 10.Only 7 centers(7/42,16.7%）reported having dedicated funding support.The top three challenges were：training sessions occupying instructors’personal time（27/42，64.3%），low instructor compensation（16/42，38.1%），and issues with the data submission system（16/42，38.1%）.Conclusion:Pediatric life support training centers in China are primarily children’s hospitals，with a geographical concentration in coastal areas，which is also reflected in the distribution of training scale and instructor resources.Most centers have relatively small training scales and limited instructor capacity，with many instructors conducting training during their personal time.These issues may hinder the implementation and effectiveness of training programs.

Hepatic stellate cells (HSCs) are the primary fibrogenic cells in the liver, and their activation plays a crucial role in the development and progression of hepatic fibrosis. Here, we report that retinoid X receptor-alpha (RXRα), a unique member of the nuclear receptor superfamily, is a key modulator of HSC activation and liver fibrosis. RXRα exerts its effects by modulating calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-mediated activation of AMP-activated protein kinase-alpha (AMPKα). In addition, we demonstrate that K-80003, which binds RXRα by a unique mechanism, effectively suppresses HSC activation, proliferation, and migration, thereby inhibiting liver fibrosis in the CCl₄ and amylin liver NASH (AMLN) diet animal models. The effect is mediated by AMPKα activation, promoting mitophagy in HSCs. Mechanistically, K-80003 activates AMPKα by inducing RXRα to form condensates with CaMKKβ and AMPKα via a two-phase process. The formation of RXRα condensates is driven by its N-terminal intrinsic disorder region and requires phosphorylation by CaMKKβ. Our results reveal a crucial role of RXRα in liver fibrosis regulation through modulating mitochondrial activities in HSCs. Furthermore, they suggest that K-80003 and related RXRα modulators hold promise as therapeutic agents for fibrosis-related diseases.