BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).

Arginine methylation is a critical post-translational modification that plays multifaceted biological functions. However, the manipulation of protein arginine methylation largely depends on genetic or pharmaceutic inhibition of the regulatory enzymes, protein arginine methyltransferases (PRMTs), or non-methylation substitution of corresponding arginine residue to lysine or alanine of protein of interest (POI), which inevitably affects other substrates, or disrupts the structure of POI. Thus, it urges an approach to specifically modulate the arginine methylation of a POI under physiological conditions. To this end, we report the discovery of a methylation tagging system (MeTAG), that enables targeted modification of protein arginine methylation. Through bridging the methyltransferase PRMT5 proximity to a POI, MeTAG facilitates the arginine methylation of POIs, including known arginine methylated proteins, androgen receptor (AR) and protein kinase B (AKT), as well as a neo-substrate E1A binding protein (p300), in a reversible and PRMT5-dependent manner. Moreover, MeTAG can regulate downstream signaling in a methylation dependent manner, leading to downregulation of PSMA mRNA level and activation of AKT. Therefore, MeTAG represents a feasible approach to modulate protein methylation and thereby perturbs protein function in biological and therapeutic contexts.

Objective:To explore the effect of scalp electroacupuncture (EA) on central pain sensitization in rats with knee osteoarthritis (KOA).Methods:Thirty-two 8-week-old female Sprague-Dawley rats were randomly divided into a blank control group, a model group, an electroacupuncture (EA) group and a sham EA group, each of 8. All of the rats except those in the control group had KOA induced through intra-articular monosodium iodoacetate injections in the right knee. Two weeks later the EA group rats began receiving daily head EA sessions 6 days/week for 2 weeks. The sham EA group received identical but non-therapeutic stimulation. The blank control and model groups received no EA intervention. Before the modelling and 3, 7, 14, 21 and 28 days later, all of the rats completed bipedal balance pain tests and mechanical allodynia evaluations. After the testing on day 28, all of the rats were euthanized for molecular analyses. Western blotting and immunohistochemistry were performed to examine protein expression of brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB), and cannabinoid receptor type 1 (CB1R) in both the periaqueductal gray (PAG) matter and spinal dorsal horns (SDHs). Serum levels of substance P (SP) and 5-hydroxytryptamine (5-HT) were also quantified using enzyme-linked immunosorbent assays.Results:Three days after successful modeling, the average weight-bearing capacity of the right hind limb in the model, sham EA and EA groups was significantly lower than that of the blank controls. It reached its lowest level on the 14th day after modeling. Concurrently, the pain responses in those three groups were significantly higher than among the controls, also peaking on the 14th day after modeling. After two weeks of electroacupuncture, the electroacupuncture group showed significant improvement in both right hind limb weight-bearing capacity and pain response compared to the model group. Meanwhile, the levels of BDNF and TrkB protein in the periaqueductal gray matter were significantly higher in the model group than among the blank controls, while the electroacupuncture group exhibited significantly reduced expression of BDNF and TrkB proteins compared to the model group, along with significantly increased CB1R protein expression. The model group showed significantly elevated expression of both BDNF and TrkB proteins in the spinal dorsal horn compared to the blank control group, while there were significant differences between the EA and model groups in the expression of BDNF, TrkB and CB1R proteins. Immunohistochemical analysis on day 28 revealed that the EA group had significantly fewer BDNF- and TrkB-positive cells in the PAG compared to the model group, with significantly more CB1R-positive cells. In the SDH, the model group exhibited significantly increased numbers of BDNF- and TrkB-positive cells compared to the blank control group, whereas significant differences were found between the EA and blank control groups in the numbers of BDNF-, TrkB- and CB1R-positive cells. Serum analysis on day 28 demonstrated that substance P and 5-hydroxytryptamine levels in the model, sham EA and EA groups were significantly higher than in the blank control group, on average. However, no significant differences were observed in serum SP and 5-HT levels between the EA and model groups.Conclusions:Scalp EA significantly alleviates central pain sensitization in KOA, at least in rats, potentially by suppressing BDNF and TrkB expression while upregulating CB1R expression in the PAG matter and the SDH.

Objective To evaluate the effectiveness of different tip positions applied to midline catheters(MC)and provide evidence-based evidence for venous catheter tip positioning in clinical practice.Methods Computerized searches of PubMed,Web of Science,Embase,Cochrane Library,CINAHL,CNKI,Wanfang Database,VIP,and CBM for studies on the effectiveness of applying MC with different tip positions were performed from the time of database construction to July 2024.Meta-analysis was performed using Rev Man 5.3 software after 2 investigators independently screened the studies,extracted the information and evaluated the quality of the included studies.Results A total of 9 studies with 2 302 hospitalized patients were included.The quality evaluation results of the included studies are all B-level.Meta-analysis showed that when the tip of the MC was located in the subclavian vein compared with the tip of the MC in the axillary vein,the rate of total catheter-related complications,phlebitis,blood leakage,infiltration,catheter occlusion,catheter dislocation,and catheter-associated thrombosis were lower,with a statistically significant difference(P＜0.05).When the tip of the MC was located in the subclavian vein compared with the tip of the MC in the axillary vein,the catheter retention time was longer,with a statistically significant difference(P=0.007).The descriptive analysis showed a lower rate of extubation due to complications when the tip of the MC was located in the subclavian vein compared with when the tip was located in the axillary vein(P＜0.05).Conclusion When the tip of the MC is located in the subclavian vein compared to when it is located in the axillary vein,the incidence of total catheter-related complications,phlebitis,blood leakage,infiltration,catheter occlusion,catheter dislocation,catheter-associated thrombosis,and the rate of catheter extractions due to complications were lower,and the catheter was left in place for a longer period of time.Due to the limitations of the quantity and quality of the included studies,more large-sample,high-quality studies are needed to further validate the effectiveness of different tip positions of MC.

ObjectiveThe U6 promoter is an essential element for driving sgRNA expression in the clustered regularly interspaced short palindromic repeat sequences/CRISPR-associated protein 9（CRISPR/Cas9）gene editing system in dicotyledonous plants. Endogenous U6 promoters typically exhibit higher transcriptional activity， which can significantly improve gene editing efficiency. This study aims to identify endogenous U6 promoters in Artemisia annua to optimize its CRISPR/Cas9 gene editing system， which holds significant importance for its molecular breeding. MethodsOn the basis of the highly conserved U6 snRNA sequences in Arabidopsis thaliana， endogenous U6 promoters were screened in the A. annua genome. Expression vectors were constructed with candidate AaU6 promoter driving the firefly luciferase （LUC） reporter gene， and then transiently transformed into Nicotiana benthamiana. Transcriptional activities of the promoters were measured and compared by in vivo imaging and the Dual Luciferase Reporter assay. ResultsEight endogenous U6 promoters were successfully cloned from A. annua. Sequences alignment revealed that all these promoters contained the two conserved cis-acting elements， upstream sequence element （USE） and TATA-box， which affected their transcriptional activity. Dual-luciferase activity assays indicated that the transcriptional activities of AaU6-3， AaU6-1， and AaU6-5 were significantly higher than that of the Arabidopsis AtU6-26 promoter， with AaU6-3 exhibiting the highest activity. ConclusionThis study identified three endogenous AaU6 promoters with high transcriptional activity in A. annua， providing key functional elements for establishing an efficient gene editing system in A. annua. These findings will contribute to advancing precision molecular breeding and high-quality germplasm innovation in A. annua.

Purpose To investigate the feasibility of a deep learning framework to automatically analyze echocardiographic color Doppler videos in detecting valvular regurgitation.Materials and Methods This study retrospectively collected echocardiographic images of 1 109 patients with valvular regurgitation in the Fourth Medical Center of PLA General Hospital,from June 2015 to September 2019 as the training and validation sets.A prospective continuous collection of 1 562 echocardiography images was used as the test set in the Fourth Medical Center of PLA General Hospital from May 13 to June 13,2023,including 378 cases of mitral regurgitation and 223 cases of aortic regurgitation.This study developed deep learning networks to establish view classification model and valvular regurgitation recognition model,including the efficiency of section classification of deep learning models.Results The deep learning view classification model in this study could automatically identify two views for diagnosing mitral regurgitation and aortic regurgitation.The recognition accuracy for the parasternal long axis color Doppler view and the apical four chamber mitral color Doppler view was 1.00 and 0.93,respectively.The sensitivity,specificity,accuracy and area under the curve of the deep learning model for diagnosing mitral regurgitation were 0.847,0.852,0.849 and 0.930,respectively.The sensitivity,specificity,accuracy and area under the curve of the deep learning model in diagnosing aortic regurgitation were 0.857,0.861,0.859 and 0.940,respectively.Conclusion Deep learning algorithms can automatically identify valvular regurgitation and have the potential to become a screening tool for valvular heart disease.

Purpose To investigate the feasibility of a deep learning framework to automatically analyze echocardiographic color Doppler videos in detecting valvular regurgitation.Materials and Methods This study retrospectively collected echocardiographic images of 1 109 patients with valvular regurgitation in the Fourth Medical Center of PLA General Hospital,from June 2015 to September 2019 as the training and validation sets.A prospective continuous collection of 1 562 echocardiography images was used as the test set in the Fourth Medical Center of PLA General Hospital from May 13 to June 13,2023,including 378 cases of mitral regurgitation and 223 cases of aortic regurgitation.This study developed deep learning networks to establish view classification model and valvular regurgitation recognition model,including the efficiency of section classification of deep learning models.Results The deep learning view classification model in this study could automatically identify two views for diagnosing mitral regurgitation and aortic regurgitation.The recognition accuracy for the parasternal long axis color Doppler view and the apical four chamber mitral color Doppler view was 1.00 and 0.93,respectively.The sensitivity,specificity,accuracy and area under the curve of the deep learning model for diagnosing mitral regurgitation were 0.847,0.852,0.849 and 0.930,respectively.The sensitivity,specificity,accuracy and area under the curve of the deep learning model in diagnosing aortic regurgitation were 0.857,0.861,0.859 and 0.940,respectively.Conclusion Deep learning algorithms can automatically identify valvular regurgitation and have the potential to become a screening tool for valvular heart disease.

Objective:To explore the effect of scalp electroacupuncture (EA) on central pain sensitization in rats with knee osteoarthritis (KOA).Methods:Thirty-two 8-week-old female Sprague-Dawley rats were randomly divided into a blank control group, a model group, an electroacupuncture (EA) group and a sham EA group, each of 8. All of the rats except those in the control group had KOA induced through intra-articular monosodium iodoacetate injections in the right knee. Two weeks later the EA group rats began receiving daily head EA sessions 6 days/week for 2 weeks. The sham EA group received identical but non-therapeutic stimulation. The blank control and model groups received no EA intervention. Before the modelling and 3, 7, 14, 21 and 28 days later, all of the rats completed bipedal balance pain tests and mechanical allodynia evaluations. After the testing on day 28, all of the rats were euthanized for molecular analyses. Western blotting and immunohistochemistry were performed to examine protein expression of brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB), and cannabinoid receptor type 1 (CB1R) in both the periaqueductal gray (PAG) matter and spinal dorsal horns (SDHs). Serum levels of substance P (SP) and 5-hydroxytryptamine (5-HT) were also quantified using enzyme-linked immunosorbent assays.Results:Three days after successful modeling, the average weight-bearing capacity of the right hind limb in the model, sham EA and EA groups was significantly lower than that of the blank controls. It reached its lowest level on the 14th day after modeling. Concurrently, the pain responses in those three groups were significantly higher than among the controls, also peaking on the 14th day after modeling. After two weeks of electroacupuncture, the electroacupuncture group showed significant improvement in both right hind limb weight-bearing capacity and pain response compared to the model group. Meanwhile, the levels of BDNF and TrkB protein in the periaqueductal gray matter were significantly higher in the model group than among the blank controls, while the electroacupuncture group exhibited significantly reduced expression of BDNF and TrkB proteins compared to the model group, along with significantly increased CB1R protein expression. The model group showed significantly elevated expression of both BDNF and TrkB proteins in the spinal dorsal horn compared to the blank control group, while there were significant differences between the EA and model groups in the expression of BDNF, TrkB and CB1R proteins. Immunohistochemical analysis on day 28 revealed that the EA group had significantly fewer BDNF- and TrkB-positive cells in the PAG compared to the model group, with significantly more CB1R-positive cells. In the SDH, the model group exhibited significantly increased numbers of BDNF- and TrkB-positive cells compared to the blank control group, whereas significant differences were found between the EA and blank control groups in the numbers of BDNF-, TrkB- and CB1R-positive cells. Serum analysis on day 28 demonstrated that substance P and 5-hydroxytryptamine levels in the model, sham EA and EA groups were significantly higher than in the blank control group, on average. However, no significant differences were observed in serum SP and 5-HT levels between the EA and model groups.Conclusions:Scalp EA significantly alleviates central pain sensitization in KOA, at least in rats, potentially by suppressing BDNF and TrkB expression while upregulating CB1R expression in the PAG matter and the SDH.

Objective:To construct an infectious clone of a Chinese HIV-1 CRF01_AE epidemic strain with strong replication capacity，and comprehensively identify its viral phenotype and replication capacity.Methods:Using the CRF01_AE clinical isolate GX2005002，which was previously isolated from whole blood of an HIV-1-infected individual in China by our laboratory，as the parental strain，the full-length genome of the virus（9.7 kb）was divided into 5' half fragment（5.1 kb）and 3' half fragment（4.6 kb）for amplification. The proviral DNA was used as a template to amplify the virus genome，which was then ligated into the eukaryotic expression vector pEASY-T1. The consistency of its sequence with the parental strain sequence was identified through full-length genome sequencing and phylogenetic analysis. The replication capacity，syncytium inducibility，and cell tropism were experimentally identified to determine its phenotypic consistency with the parental strain.Results:An infectious clone of the CRF01_AE strain was successfully constructed，and its genome sequence exhibited high consistency with the sequence of the parental strain. By transfecting target cells，a derivative virus with infectious activity and replication capability was successfully rescued. The derived virus maintained phenotypic characteristics consistent with the parental strain，such as cell tropism and syncytium inducibility.Conclusion:This study successfully constructed an infectious clone of a Chinese HIV-1 CRF01_AE epidemic strain with clear background and distinct phenotype. The genomic sequence and viral phenotypic characteristics of the derived virus are basically consistent with the parental strain，providing strong representation of the original isolate and serving as a powerful tool for research on the correlation between the genetic characteristics，viral phenotype，and pathogenicity of HIV-1 CRF01_AE strains.

Objective:To explore the efficacy and feasibility of hypomethylating agent (HMA) as preventive therapy in children with high-risk acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods:A retrospective cohort study. Data from 173 children who underwent allo-HSCT for high-risk AML at Children′s Hospital of Soochow University between August 2019 and April 2023 were analyzed. Participants were categorized into a trial group receiving HMA and a control group. Further classification was based on HMA courses:≥4 and <4 courses. The efficacy and safety of HMA preventive treatment after allo-HSCT were evaluated. Survival analysis was performed using the Kaplan-Meier method with Log-Rank testing, the Fine-Gray model was used to assess cumulative relapse rates and Cox regression was used to identify prognostic factors. Adverse events during HMA were descriptively analyzed.Results:Among 173 patients, there were 100 males (57.8%) and 73 females (42.2%), with the age of 81 (34,127) months. The starting time of HMA was 123 (91, 191) d post-transplant, continuing 4.0 (3.0, 6.5) courses and the follow-up period was 24 (13, 32) months. The trial group (53 cases) showed better 2-year overall survival (OS) rate ((88.6±5.6)% vs. (76.6±4.3)%, χ 2=5.00, P=0.025) and relapse-free survival (RFS) rate ((89.2±4.7)% vs. (56.2±4.8)%, χ 2=15.75, P<0.001) than control group (120 cases). The 2-year OS rates and RFS rates were similar between ≥4 courses group (31 cases) and <4 courses group (22 cases)(both P>0.05). The cumulative relapse rate in the trial group was significantly lower ((10.8±0.2)% vs. (35.2±0.2)%, χ 2=10.84, P=0.001) than control group. Among children with molecular relapse, 8 cases (8/30, 26.7%) in the control group had hematological relapse compared to 1 case (1/2) in the trial group ( χ 2=0.81, P=0.369). The differences in incidence of acute and chronic graft-versus-host disease (GVHD) were not statistically significant (all P>0.05). Cox regression analysis revealed that minimal residual disease (MRD) positivity detected by flow cytometry before allo-HSCT and chronic GVHD were independent risk factors for OS (both P<0.05).The HMA preventive treatment was an independent protective factor for RFS, while age ≥10 years and MRD positivity detected by PCR before allo-HSCT were independent risk factors for RFS (all P<0.05). In trial group, 38 cases experienced grade 3 to 4 adverse events (71.7%). Conclusion:HMA is safe as preventive treatment in post-transplant children with high-risk AML, which can reduce the relapse risk and doesn't increase the risk of GVHD.