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).

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 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 elucidate the prognostic differences and risk factors associated with different patterns of recurrence and metastasis following pancreatic cancer (PC) resection.Methods:This is a retrospective case series study. Clinicopathological data and follow-up information were retrospectively collected from 210 patients who underwent surgery for PC at the Department of Hepatobiliary and Pancreatic Surgery, Peking University First Hospital, between January 2014 and December 2023. There were 114 males and 96 females; the age was (64.5±10.3) years (range: 29 to 89 years). Survival functions based on different times to recurrence and metastasis and different patterns of recurrence and metastasis were estimated using the Kaplan-Meier method, and survival differences among groups were compared using the Log-rank test. Identifying the optimal cutoff for time to postoperative recurrence/metastasis predicting overall survival (OS) in pancreatic cancer patients via the minimum p-value approach. Univariate and multivariate Cox regression analyses were performed to identify independent risk factors affecting OS following pancreatectomy.Results:A total of 210 patients met the inclusion and exclusion criteria. Among them, 71 patients remained free of recurrence and metastasis, while 139 developed recurrence and metastasis. The patterns included local recurrence ( n=34), liver metastasis ( n=39), lung metastasis ( n=11), peritoneal metastasis ( n=13), multiple sites metastasis ( n=38), bone metastasis ( n=3), and kidney metastasis ( n=1). OS was significantly shorter in the group with postoperative recurrence and metastasis compared to the group without recurrence/metastasis (23.07 months vs.not reached, P<0.01). The optimal cut-off time distinguishing early from late recurrence and metastasis was 13 months. There was a significant difference in post-recurrence survival between patients with early and late recurrence and metastasis (16.03 months vs. 52.40 months, P=0.009). The Kaplan-Meier survival curve showed that different postoperative recurrence and metastasis patterns had different impacts on OS, with lung metastasis showing the best prognosis compared to local recurrence, liver metastasis, peritoneal metastasis, and multiple sites metastasis ( P<0.01). Multivariate Cox analysis revealed that Eastern Cooperative Oncology Group (ECOG) score 1, postoperative carcinoembryonic antigen (CEA) ≥15 μg/L, poor tumor differentiation, postoperative local recurrence, liver metastasis, peritoneal metastasis, and multiple sites metastases are independent risk factors for postoperative recurrence and metastasis (all P<0.05). Conclusions:Considerable prognostic heterogeneity exists in postoperative PC patients depending on the site and pattern of recurrence or metastasis. Specifically, lung metastasis portends a significantly more favorable prognosis than liver metastasis, peritoneal metastasis, local recurrence, or multiple sites metastases. ECOG score 1, postoperative CEA≥15 μg/L, poor tumor differentiation, postoperative local recurrence, liver metastasis, peritoneal metastasis, and multiple sites metastases are independent risk factors for OS in postoperative PC patients.

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.

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 determine hyaluronan(HA)expression in the endocrine-resistant microenvironment of estrogen receptor-positive(ER+)breast cancer and elucidate its impact on the acquired resistance.Methods·Chemiluminescent immunoassay was used to quantify HA levels in the culture supernatants of fulvestrant-resistant breast cancer cells.An immunofluorescence(IF)assay was performed to visualize the colocalization of CD44 and HA in MCF7/FulR cells.Using an established adaptive endocrine-resistant breast cancer mouse model,HA expression in resistant breast cancer tissues was assessed by immunohistochemistry(IHC)assay.Single-cell RNA sequencing(scRNA-seq)and RNA sequencing(RNA-seq)were conducted to examine transcriptomic profiles and alterations in HA-related genes in resistant breast cancer cells.Flow cytometry(FCM)was utilized to measure the proportion of CD44+CD24-cells in MCF7/FulR.The correlation between HA synthesis genes and cell stemness was investigated in clinical ER+breast cancers from GEO data sets.Hyaluronidase(HAase)treatment was applied to remove the"HA coat",and RT-qPCR and Western blotting analysis were carried out to monitor changes in stemness-related molecules.CCK-8 assays,flow cytometry(FCM),and Hoechst 33258 staining were performed to determine changes in apoptosis and fulvestrant efficiency after HAase treatment.Results·IF results revealed that compared with MCF7 cells,the"HA coat"on the surface of MCF7/FulR cells was significantly thickened.IHC demonstrated markedly increased HA retention in fulvestrant-resistant mouse breast cancer tissues.ScRNA-seq and RNA-seq analyses indicated elevated expression of stemness-related genes and HA synthesis-associated genes in fulvestrant-resistant breast cancer cells.Correlation analysis revealed a positive association between HA synthesis and cancer stemness in ER+breast cancer.IF and RT-qPCR results demonstrated that removing the HA coating from the surface of MCF7/FulR cells led to a significant reduction in the expression of stemness-related molecules;concurrently,CCK-8 assays,FCM analysis,and Hoechst 33258 staining revealed that"HA coat"clearance reduced MCF7/FulR'tolerance to fulvestrant and increased apoptosis.Conclusion·Endocrine-resistant breast cancer cells develop an enriched"HA coat",which promotes stemness in fulvestrant-resistant tumors.Disruption of this HA coat through HAase treatment effectively reduces cell stemness,induces apoptosis,and re-sensitizes breast cancer cells to fulvestrant.

Objective:To evaluate the efficacy and safety of cord blood stem cell transplantation (CBSCT) in pediatric recipients with mucopolysaccharidosis type Ⅱ (MPS Ⅱ, Hunter syndrome).Methods:Clinical data of five male children with MPS Ⅱ who underwent CBSCT at the Department of Hematology, Children's Hospital of Soochow University between March 2018 and July 2023 were retrospectively analyzed. Post-transplantation clinical outcomes and enzymatic activity were observed. Literature was searched in the China National Knowledge Infrastructure (CNKI), Wanfang, and PubMed databases using the keywords "mucopolysaccharidosis type Ⅱ" "MPS Ⅱ" "IDS gene" and "Hunter syndrome" in both English and Chinese. Articles describing clinical manifestations, genetic diagnosis, and hematopoietic stem cell transplantation (HSCT) in MPS II were screened.Results:All five patients were male, with a median age at diagnosis of 4.3(2.5-5.5) years and a median age at transplantation of 4.6(2.8-6.5) years. At diagnosis, all exhibited coarse facial features, hepatosplenomegaly, skeletal deformities or abnormalities, abnormal head MRI findings, and Mongolian spots; four had joint stiffness, three had valvular heart disease, and two had airway obstruction, short stature, and intellectual disability. Three recipients received single-unit cord blood, and two received double-unit cord blood. Myeloablative conditioning regimens consisted of busulfan, cyclophosphamide, anti-thymocyte globulin ± fludarabine. The median neutrophil engraftment and platelet engraftment times were 19(14-21) days and 26(15-44) days, respectively. Complete donor chimerism was achieved at 1 month post-transplantation. Complications included peri-engraftment syndrome in 5 cases, acute graft-versus-host disease (GVHD) in 2 cases (1 with grade Ⅳ skin and grade Ⅱ intestinal involvement; 1 with grade Ⅱ skin involvement), limited chronic GVHD in 1 case (moderate intestinal involvement), cytomegalovirus (CMV) infection in 3 cases, Epstein-Barr virus (EBV) infection in 1 case, and capillary leak syndrome in 1 case; all were successfully managed. At the last follow-up in December 2023, all patients were alive, and enzyme activity had normalized by 3 months post-transplantation. Most clinical symptoms and signs improved; however, neurocognitive function showed no significant improvement, and some recipients exhibited progressive brain parenchymal changes on MRI. Literature review included 7 English and 5 Chinese studies, indicating that CBSCT and other HSCT modalities can improve multi-system clinical manifestations in MPS Ⅱ children, including restoration of enzyme activity, organ function improvement (such as liver and spleen shrinkage, adenoid reduction), enhanced motor function, and stabilization of neurocognitive function. Some studies suggest superior efficacy compared with enzyme replacement therapy, particularly in delaying disease progression and improving daily living abilities.Conclusion:CBSCT effectively restores enzymatic activity and improves multi-system manifestations in children with MPS Ⅱ, although its effect on neurological symptoms remains controversial. It is a safe and feasible therapeutic option for this condition.

Objective:To evaluate the clinical efficacy of haploidentical hematopoietic stem cell transplantation (haplo-HSCT) in treating pediatric Diamond-Blackfan anemia (DBA).Method:Clinical data of five pediatric DBA recipients who underwent haplo-HSCT at the Children's Hospital of Soochow University between June 2018 and June 2023 were retrospectively analyzed. The conditioning regimen comprised a backbone protocol of fludarabine, busulfan, and rabbit anti-human thymocyte immunoglobulin (Bu+Flu+ATG), with optional cyclophosphamide, rituximab, or thiotepa. Post-transplant prophylaxis for graft-versus-host disease (GVHD) included cyclosporine A/tacrolimus combined with mycophenolate mofetil and methotrexate. Outcome measures included neutrophil and platelet engraftment times, hematopoietic reconstitution, incidence and severity of post-transplant complications, hemoglobin maintenance, and survival status. Literature was searched in CNKI, Wanfang, and PubMed using the keywords "Diamond-Blackfan anemia" "DBA" and "haplo-HSCT" in both English and Chinese.Result:The median age at transplantation was 61 months. Human leukocyte antigen (HLA) matching ranged from 5-8/10 loci. Stem cell sources included bone marrow alone (1 case), bone marrow plus peripheral blood stem cells (PBSCT, 2 cases), umbilical cord blood (CB-HSCT, 1 case), and PBSCT combined with CB-HSCT (1 case). All five recipients achieved successful engraftment with complete hematopoietic and immune reconstitution. Median neutrophil and platelet engraftment times were 11 days and 9 days, respectively, with erythroid reconstitution at 25 days post-transplant. Complications included grade IV acute GVHD (aGVHD) in one recipient, grade I aGVHD in two recipients, and chronic GVHD (cGVHD) in one recipient. Cytomegalovirus (CMV) infection occurred in three cases, and Epstein-Barr virus (EBV) infection in one case, all of which resolved with ganciclovir. No other transplant-related complications were reported. At a median follow-up of 44.8(4.8-59.2) months, all recipients were alive with sustained erythroid reconstitution and disease-free survival. Literature review (six studies) confirmed HSCT as an effective treatment for DBA, with prognosis closely related to age at transplantation, conditioning regimens, and donor selection.Conclusion:Haplo-HSCT can be considered as a viable treatment option for pediatric DBA recipients.

Aiming at solving problems of ambiguous objectives,fragmented contents,fossilized forms,and single assess-ments in ideological and political education,a new course pattern have been constructed based on reestablishing course objectives,re-constructing teaching contents and resources,and reforming teaching models and evaluation systems through transition of course con-cept and promotion of online-and offline-blended course.Considering culture features of Immunology,diverse teaching activities were implemented.A cultural atmosphere of"happy learning,beauty orienting,thought discriminating,and practice devoting"have been created and the goal of ideological and political education with definite objectives,systematic contents,various forms,and multiple as-sessments have been archived.At the end of the term,a survey on the teaching effects of ideological and political education revealed that 99.3%of students felt moved,touched,and gained a lot during the ideological and political education.Remodeling the curriculum culture blazes a new path for ideological and political education in Medical Immunology.