BACKGROUND: T cell dysfunction, which includes exhaustion, anergy, and senescence, is a distinct T cell differentiation state that occurs after antigen exposure. Although T cell dysfunction has been a cornerstone of cancer immunotherapy, its potential in transplant research, while not yet as extensively explored, is attracting growing interest. Interferon regulatory factor 4 (IRF4) has been shown to play a pivotal role in inducing T cell dysfunction. METHODS: A novel ultra-low-dose combination of Trametinib and Rapamycin, targeting IRF4 inhibition, was employed to investigate T cell proliferation, apoptosis, cytokine secretion, expression of T-cell dysfunction-associated molecules, effects of mitogen-activated protein kinase (MAPK) and mammalian target of rapamycin (mTOR) signaling pathways, and allograft survival in both in vitro and BALB/c to C57BL/6 mouse cardiac transplantation models. RESULTS: In vitro , blockade of IRF4 in T cells effectively inhibited T cell proliferation, increased apoptosis, and significantly upregulated the expression of programmed cell death protein 1 (PD-1), Helios, CD160, and cytotoxic T lymphocyte-associated antigen (CTLA-4), markers of T cell dysfunction. Furthermore, it suppressed the secretion of pro-inflammatory cytokines interferon (IFN)-γ and interleukin (IL)-17. Combining ultra-low-dose Trametinib (0.1 mg·kg -1 ·day -1 ) and Rapamycin (0.1 mg·kg -1 ·day -1 ) demonstrably extended graft survival, with 4 out of 5 mice exceeding 100 days post-transplantation. Moreover, analysis of grafts at day 7 confirmed sustained IFN regulatory factor 4 (IRF4) inhibition, enhanced PD-1 expression, and suppressed IFN-γ secretion, reinforcing the in vivo efficacy of this IRF4-targeting approach. The combination of Trametinib and Rapamycin synergistically inhibited the MAPK and mTOR signaling network, leading to a more pronounced suppression of IRF4 expression. CONCLUSIONS Targeting IRF4, a key regulator of T cell dysfunction, presents a promising avenue for inducing transplant immune tolerance. In this study, we demonstrate that a novel ultra-low-dose combination of Trametinib and Rapamycin synergistically suppresses the MAPK and mTOR signaling network, leading to profound IRF4 inhibition, promoting allograft acceptance, and offering a potential new therapeutic strategy for improved transplant outcomes. However, further research is necessary to elucidate the underlying pharmacological mechanisms and facilitate translation to clinical practice.
Animals ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Interferon Regulatory Factors/metabolism* ; Heart Transplantation/methods* ; T-Lymphocytes/immunology* ; Sirolimus/therapeutic use* ; Pyridones/therapeutic use* ; Graft Survival/drug effects* ; Pyrimidinones/therapeutic use* ; Cell Proliferation/drug effects* ; Apoptosis/drug effects* ; Male ; Signal Transduction/drug effects*

One of the basic questions in the aging field is whether there is a fundamental difference between the aging of lower invertebrates and mammals. A major difference between the lower invertebrates and mammals is the abundancy of noncoding RNAs, most of which are not conserved. We have previously identified a noncoding RNA Terc-53 that is derived from the RNA component of telomerase Terc. To study its physiological functions, we generated two transgenic mouse models overexpressing the RNA in wild-type and early-aging Terc-/- backgrounds. Terc-53 mice showed age-related cognition decline and shortened life span, even though no developmental defects or physiological abnormality at an early age was observed, indicating its involvement in normal aging of mammals. Subsequent mechanistic study identified hyaluronan-mediated motility receptor (Hmmr) as the main effector of Terc-53. Terc-53 mediates the degradation of Hmmr, leading to an increase of inflammation in the affected tissues, accelerating organismal aging. adeno-associated virus delivered supplementation of Hmmr in the hippocampus reversed the cognition decline in Terc-53 transgenic mice. Neither Terc-53 nor Hmmr has homologs in C. elegans. Neither do arthropods express hyaluronan. These findings demonstrate the complexity of aging in mammals and open new paths for exploring noncoding RNA and Hmmr as means of treating age-related physical debilities and improving healthspan.
Animals ; Mice ; RNA, Untranslated/metabolism* ; Aging/genetics* ; Mice, Transgenic ; Telomerase/metabolism* ; RNA/genetics* ; Hippocampus/metabolism* ; Humans ; Mice, Inbred C57BL

Objective:To explore the binding characteristics of N, N-diethyl-2-(2-(4-(2- 18F-fluoroethoxy)phenyl)-5, 7-dimethylpyrazolo[1, 5-a]pyrimidin-3-yl)acetamide ( 18F-DPA-714) and ( R)- N-sec-butyl- N-methyl-4-(3-( 18F-trifluoromethyl)phenyl)quinazoline-2-carboxamide ( 18F-TFQC) to the single nucleotide polymorphisms of the 18×10 3 translocator protein (TSPO), and to evaluate the imaging efficacy and feasibility of those 2 molecular probes in neuroinflammation rat models. Methods:To test the selectivity of 18F-DPA-714 and 18F-TFQC for TSPO polymorphisms, the wild-type (high-affinity binding, HAB) and mutant (low-affinity binding, LAB) sequences of the human TSPO gene were transfected into 293T cells respectively. A competitive inhibition assay was carried out with N-methyl- N-(1-methylpropyl)-1-(2-chlorophenyl)-3-isoquinoline carboxamide (PK11195) as an inhibitor to determine the binding affinities of 2 probes to TSPO polymorphisms. Rat neuroinflammation models ( n=6) were established using lipopolysaccharide. Three days after modeling, small animal PET/CT imaging was performed using 18F-DPA-714 and 18F-TFQC, respectively, to observe and compare the uptake of the tracers, and the ratio of SUV mean of the right striatum to SUV mean of the left striatum (SUVR) was calculated. After the imaging, the expression and distribution of microglia and TSPO were detected by tissue immunofluorescence. Repeated-measures analysis of variance was used to analyze the SUVR data of different groups. Results:The inhibition constants ( Ki) of 18F-TFQC on 293T-LAB and 293T-HAB cells were 23.51 and 14.60 nmol/L, respectively, with a Ki LAB/ Ki HAB ratio of 1.61, indicating low sensitivity to TSPO single nucleotide polymorphisms. The Ki of 18F-DPA-714 for binding to 293T-LAB and 293T-HAB cells were 45.23 and 6.47 nmol/L, respectively, with a Ki LAB/ Ki HAB ratio of 6.99. Small animal PET/CT imaging demonstrated that specifically uptake of both probes could be found in neuroinflammatory lesions. The overall SUVR of 18F-DPA-714 in the lesions within 60minutes was slightly higher than that of 18F-TFQC, but no significant difference was observed ( F values: inter-group 0.40, time effect 0.30, cross-effect 0.03; all P>0.05). Conclusions:Compared with 18F-DPA-714, 18F-TFQC is less sensitive to TSPO gene polymorphisms, thus being more suitable for clinical application and promotion. It holds promise for the early identification of neuroinflammation and the efficacy monitoring of anti-inflammatory drug treatments.

The incomplete degradation of tumour cells by macrophages (Mϕ) is a contributing factor to tumour progression and metastasis, and the degradation function of Mϕ is mediated through phagosomes and lysosomes. In our preliminary experiments, we found that overactivation of NADPH oxidase 2 (NOX2) reduced the ability of Mϕ to degrade engulfed tumour cells. Above this, we screened out liquiritin from Glycyrrhiza uralensis Fisch, which can significantly inhibit NOX2 activity and inhibit tumours, to elucidate that suppressing NOX2 can enhance the ability of Mϕ to degrade tumour cells. We found that the tumour environment could activate the NOX2 activity in Mϕ phagosomes, causing Mϕ to produce excessive reactive oxygen species (ROS), thus prohibiting the formation of phagolysosomes before degradation. Conversely, inhibiting NOX2 in Mϕ by liquiritin can reduce ROS and promote phagosome-lysosome fusion, therefore improving the enzymatic degradation of tumour cells after phagocytosis, and subsequently promote T cell activity by presenting antigens. We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox, blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox, thereby inhibiting the activity of NOX2. This study elucidates the specific mechanism by which Mϕ cannot degrade tumour cells after phagocytosis, and indicates that liquiritin can promote the ability of Mϕ to degrade tumour cells by suppressing NOX2.

The incomplete degradation of tumour cells by macrophages(Mφ)is a contributing factor to tumour progression and metastasis,and the degradation function of Mφ is mediated through phagosomes and lysosomes.In our preliminary experiments,we found that overactivation of NADPH oxidase 2(NOX2)reduced the ability of Mφ to degrade engulfed tumour cells.Above this,we screened out liquiritin from Glycyrrhiza uralensis Fisch,which can significantly inhibit NOX2 activity and inhibit tumours,to elucidate that suppressing NOX2 can enhance the ability of Mφ to degrade tumour cells.We found that the tumour environment could activate the NOX2 activity in Mφ phagosomes,causing Mφ to produce excessive reactive oxygen species(ROS),thus prohibiting the formation of phagolysosomes before degradation.Conversely,inhibiting NOX2 in Mφ by liquiritin can reduce ROS and promote phagosome-lysosome fusion,therefore improving the enzymatic degradation of tumour cells after phagocytosis,and subse-quently promote T cell activity by presenting antigens.We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox,blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox,thereby inhibiting the activity of NOX2.This study elucidates the specific mechanism by which Mφ cannot degrade tumour cells after phagocytosis,and indicates that liquiritin can promote the ability of Mφ to degrade tumour cells by suppressing NOX2.

Objective To develop a nomogram-based predictive model for assessing the risk of respiratory distress syndrome(RDS)in premature infants in the high-altitude region of Dali.The predictive performance and clinical applicability of the model will be systematically evaluated to provide evidence-based guidance for the early diagnosis and clinical management of respiratory distress in premature infants.Methods A total of 680 preterm infants admitted to the Dali Maternal and Child Health Hospital between January 2020 and December 2024 were enrolled in the study and randomly divided into a training set(n=476)and a validation set(n=204)at a ratio of 7∶3.Independent predictors were identified through univariate logistic regression and multivariate stepwise regression analyses,and a nomogram model was subsequently developed using R software.The performance of the model,including its discrimination,calibration,stability,and clinical applicability,was evaluated using the receiver operating characteristic curve(ROC),Hosmer-Lemeshow goodness-of-fit test,bootstrap resampling method,and decision curve analysis(DCA).Results The final model incorporated seven independent variables:gestational age,birth weight,Apgar score,blood oxygen saturation,gestational hyperglycemia,prenatal glucocor-ticoid therapy,and maternal history of infection.The areas under the curve(AUCs)for the training and validation sets were 0.88(95%CI:0.84～0.92)and 0.83(95%CI:0.76～0.89),respectively,with all Hosmer-Lemeshow test p-values exceeding 0.05.The bootstrap-corrected AUC was 0.85(95%CI:0.81～0.89).DCA indicated that the model achieved the highest net benefit at a risk threshold range of 10%to 35%.Conclusions This model integrates multiple risk factors associated with the occurrence of RDS in plateau environments,demonstrating robust predictive performance for RDS in preterm infants residing in high-altitude areas such as Dali.It can serve as a valuable tool for risk stratification and clinical decision-making,and may also provide a reference for future multicenter prospective studies.

Objective:To compare the clinical outcomes of thoracic endovascular aortic repair (TEVAR) using self-radiopaque marker guided physician modified fenestration with stent-graft in situ fenestration technology with or without the implantation of branch stents for the treatment of aortic arch diseases.Methods:The clinical data of 653 patients with aortic arch diseases who underwent TEVAR using fenestration from Dec 2015 to Jun 2023 at two vascular surgery centers were retrospectively analyzed.Results:A total of 454 patients received branch stent implantation, while 199 did not. The incidence of non-aortic-related complications within 30 days post-operation was higher in the branch stent implantation group compared to the non-implantation group (8.6% vs. 3.5%, P=0.020). The overall follow-up rate was 93.8%, with median follow-up time of 37 months and 52 months for the branch stent implantation group and non-implantation group, respectively. Kaplan-Meier survival analysis showed no significant statistical difference between the two groups in terms of cumulative all-cause survival ( P=0.223), free from endoleak ( P=0.106), and free from branch artery occlusion ( P=0.130). Conclusions:The implantation of branch stents following in situ fenestration with stent-graft technology in TEVAR did not significantly affect overall survival, endoleak incidence, or branch artery occlusion rates in patients with aortic arch diseases. Therefore, the decision to implant branch stents should be tailored according to the specific pathology and anatomical characteristics of the aortic arch.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective:To explore the binding characteristics of N, N-diethyl-2-(2-(4-(2- 18F-fluoroethoxy)phenyl)-5, 7-dimethylpyrazolo[1, 5-a]pyrimidin-3-yl)acetamide ( 18F-DPA-714) and ( R)- N-sec-butyl- N-methyl-4-(3-( 18F-trifluoromethyl)phenyl)quinazoline-2-carboxamide ( 18F-TFQC) to the single nucleotide polymorphisms of the 18×10 3 translocator protein (TSPO), and to evaluate the imaging efficacy and feasibility of those 2 molecular probes in neuroinflammation rat models. Methods:To test the selectivity of 18F-DPA-714 and 18F-TFQC for TSPO polymorphisms, the wild-type (high-affinity binding, HAB) and mutant (low-affinity binding, LAB) sequences of the human TSPO gene were transfected into 293T cells respectively. A competitive inhibition assay was carried out with N-methyl- N-(1-methylpropyl)-1-(2-chlorophenyl)-3-isoquinoline carboxamide (PK11195) as an inhibitor to determine the binding affinities of 2 probes to TSPO polymorphisms. Rat neuroinflammation models ( n=6) were established using lipopolysaccharide. Three days after modeling, small animal PET/CT imaging was performed using 18F-DPA-714 and 18F-TFQC, respectively, to observe and compare the uptake of the tracers, and the ratio of SUV mean of the right striatum to SUV mean of the left striatum (SUVR) was calculated. After the imaging, the expression and distribution of microglia and TSPO were detected by tissue immunofluorescence. Repeated-measures analysis of variance was used to analyze the SUVR data of different groups. Results:The inhibition constants ( Ki) of 18F-TFQC on 293T-LAB and 293T-HAB cells were 23.51 and 14.60 nmol/L, respectively, with a Ki LAB/ Ki HAB ratio of 1.61, indicating low sensitivity to TSPO single nucleotide polymorphisms. The Ki of 18F-DPA-714 for binding to 293T-LAB and 293T-HAB cells were 45.23 and 6.47 nmol/L, respectively, with a Ki LAB/ Ki HAB ratio of 6.99. Small animal PET/CT imaging demonstrated that specifically uptake of both probes could be found in neuroinflammatory lesions. The overall SUVR of 18F-DPA-714 in the lesions within 60minutes was slightly higher than that of 18F-TFQC, but no significant difference was observed ( F values: inter-group 0.40, time effect 0.30, cross-effect 0.03; all P>0.05). Conclusions:Compared with 18F-DPA-714, 18F-TFQC is less sensitive to TSPO gene polymorphisms, thus being more suitable for clinical application and promotion. It holds promise for the early identification of neuroinflammation and the efficacy monitoring of anti-inflammatory drug treatments.

Objective To develop a nomogram-based predictive model for assessing the risk of respiratory distress syndrome(RDS)in premature infants in the high-altitude region of Dali.The predictive performance and clinical applicability of the model will be systematically evaluated to provide evidence-based guidance for the early diagnosis and clinical management of respiratory distress in premature infants.Methods A total of 680 preterm infants admitted to the Dali Maternal and Child Health Hospital between January 2020 and December 2024 were enrolled in the study and randomly divided into a training set(n=476)and a validation set(n=204)at a ratio of 7∶3.Independent predictors were identified through univariate logistic regression and multivariate stepwise regression analyses,and a nomogram model was subsequently developed using R software.The performance of the model,including its discrimination,calibration,stability,and clinical applicability,was evaluated using the receiver operating characteristic curve(ROC),Hosmer-Lemeshow goodness-of-fit test,bootstrap resampling method,and decision curve analysis(DCA).Results The final model incorporated seven independent variables:gestational age,birth weight,Apgar score,blood oxygen saturation,gestational hyperglycemia,prenatal glucocor-ticoid therapy,and maternal history of infection.The areas under the curve(AUCs)for the training and validation sets were 0.88(95%CI:0.84～0.92)and 0.83(95%CI:0.76～0.89),respectively,with all Hosmer-Lemeshow test p-values exceeding 0.05.The bootstrap-corrected AUC was 0.85(95%CI:0.81～0.89).DCA indicated that the model achieved the highest net benefit at a risk threshold range of 10%to 35%.Conclusions This model integrates multiple risk factors associated with the occurrence of RDS in plateau environments,demonstrating robust predictive performance for RDS in preterm infants residing in high-altitude areas such as Dali.It can serve as a valuable tool for risk stratification and clinical decision-making,and may also provide a reference for future multicenter prospective studies.