Tissue repair requires the reconstruction of functional vascular networks to restore oxygen and nutrient delivery, eliminate metabolic waste, and maintain tissue homeostasis. Although biochemical factors such as growth factors and cytokines have been extensively studied in vascular regeneration, increasing evidence indicates that mechanical signals from the extracellular matrix (ECM) are equally important regulators of angiogenesis. Matrix stiffness, as a major biomechanical property of the tissue microenvironment, provides critical information that influences endothelial cell (EC) behavior and vascular remodeling through mechanotransduction. However, the biological effects of matrix stiffness are not universally defined as either pro- or anti-angiogenic, but are highly dependent on tissue context, cellular composition, disease progression, and the dynamic changes occurring during tissue repair. Therefore, understanding how matrix stiffness regulates vascular regeneration is essential for developing more precise strategies for tissue engineering and regenerative medicine. In this review, we summarize recent advances in the regulation of angiogenesis by matrix stiffness during tissue repair from multiple perspectives. First, we discuss the direct effects of matrix stiffness on EC behaviors, including differentiation, morphological remodeling, migration, proliferation, barrier maintenance, and vascular network formation. ECs sense mechanical alterations in the surrounding matrix through various mechanosensitive structures, including integrins, focal adhesion complexes, and mechanosensitive ion channels such as Piezo1 and TRPV proteins. These mechanical signals are subsequently transmitted through intracellular pathways involving FAK, RhoA/ROCK, MAPK, and Hippo-YAP/TAZ signaling, leading to cytoskeletal reorganization and transcriptional regulation. Through these mechanisms, matrix stiffness regulates endothelial functional states and determines the balance between regenerative vascular formation and pathological vascular remodeling. Beyond the direct regulation of ECs, we further highlight the importance of stiffness-mediated intercellular communication within the regenerative microenvironment. Matrix stiffness can regulate the behavior and secretory profiles of vascular-associated cells, including mesenchymal stem cells and macrophages, thereby indirectly affecting endothelial function through paracrine mechanisms. Changes in matrix mechanics influence the secretion of angiogenic factors, inflammatory cytokines, and extracellular vesicles from these cells, creating a mechanical regulation network that coordinates vascular regeneration. This perspective extends the traditional concept of matrix stiffness from a physical support structure to an active regulatory signal that integrates multiple cellular responses during tissue repair. Furthermore, we discuss the tissue-specific effects of matrix stiffness in vascular regeneration across different organs, including the aorta, lung, liver, and heart. Although excessive matrix stiffening is frequently associated with fibrosis and vascular dysfunction, the consequences of mechanical changes vary considerably among tissues. Moderate stiffness alterations may support endothelial activation and vascular stabilization in certain regenerative contexts, whereas persistent pathological stiffening can promote inflammation, endothelial dysfunction, and impaired vascular repair. These findings emphasize that the biological meaning of “soft” and “stiff” microenvironments should be interpreted according to specific tissue and experimental conditions rather than as universal mechanical classifications. Finally, we summarize current challenges and future perspectives in this field. A major limitation is the lack of standardized mechanical characterization among different studies, as stiffness measurements are influenced by material properties, testing methods, and experimental conditions, limiting direct comparison across research systems. Moreover, most existing models fail to fully reproduce the dynamic and viscoelastic properties of native ECM during tissue regeneration. Future studies should combine advanced biomaterials with standardized mechanical analysis, organoid models, and multi-omics approaches to establish more accurate mechanical regulatory maps. Overall, this review proposes that matrix stiffness is not merely a structural feature of tissues, but an active biological signal that regulates vascular regeneration through coordinated mechanotransduction and multicellular interactions. A deeper understanding of stiffness-mediated vascular regulation will provide new theoretical insights and therapeutic opportunities for improving tissue repair outcomes.

With the rapid development of competitive sports, the incidence of anterior cruciate ligament (ACL) injury is on the rise. Such injuries may shorten athletes′ career and lead to other long-term adverse consequences. Although athletes generally recover well after ACL reconstruction, many still struggle to return to their pre-injury performance levels. Advances in the understanding of ACL anatomy and injury mechanisms, along with the evolution of surgical techniques and rehabilitation methods, have provided more individualized and tailored options for athletes following ACL injuries. However, there is currently no consensus in China regarding surgical and rehabilitation strategies for competitive athletes aiming to return to sports after ACL injuries. To this end, the Sports Medicine Committee of the Chinese Research Hospital Association and the Editorial Board of the Chinese Journal of Trauma jointly formulated the Expert consensus on surgical treatment and rehabilitation for competitive sports athletes returning to sports after anterior cruciate ligament injury ( version 2025), and presented 14 recommendations covering surgical indications, preoperative rehabilitation, surgical timing, surgical strategies and postoperative rehabilitation strategies, aiming to improve the surgical treatment and rehabilitation system for ACL injuries in competitive athletes and facilitate their return to high-level sports performance after injury.

The angiogenic response is essential for the repair of ischemic brain tissue. Integrin α6 (Itga6) expression has been shown to increase under hypoxic conditions and is expressed exclusively in vascular structures; however, its role in post-ischemic angiogenesis remains poorly understood. In this study, we demonstrate that mice with endothelial cell-specific knockout of Itga6 exhibit reduced neovascularization, reduced pericyte coverage on microvessels, and accelerated breakdown of microvascular integrity in the peri-infarct area. In vitro, endothelial cells with ITGA6 knockdown display reduced proliferation, migration, and tube-formation. Mechanistically, we demonstrated that ITGA6 regulates post-stroke angiogenesis through the PI3K/Akt-eNOS-VEGFA axis. Importantly, the specific overexpression of Itga6 in endothelial cells significantly enhanced neovascularization and enhanced the integrity of microvessels, leading to improved functional recovery. Our results suggest that endothelial cell Itga6 plays a crucial role in key steps of post-stroke angiogenesis, and may represent a promising therapeutic target for promoting recovery after stroke.
Animals ; Nitric Oxide Synthase Type III/metabolism* ; Mice ; Proto-Oncogene Proteins c-akt/metabolism* ; Integrin alpha6/genetics* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Stroke/pathology* ; Vascular Remodeling/physiology* ; Vascular Endothelial Growth Factor A/metabolism* ; Mice, Knockout ; Signal Transduction/physiology* ; Mice, Inbred C57BL ; Male ; Neovascularization, Physiologic/physiology*

With the rapid development of competitive sports, the incidence of anterior cruciate ligament (ACL) injury is on the rise. Such injuries may shorten athletes′ career and lead to other long-term adverse consequences. Although athletes generally recover well after ACL reconstruction, many still struggle to return to their pre-injury performance levels. Advances in the understanding of ACL anatomy and injury mechanisms, along with the evolution of surgical techniques and rehabilitation methods, have provided more individualized and tailored options for athletes following ACL injuries. However, there is currently no consensus in China regarding surgical and rehabilitation strategies for competitive athletes aiming to return to sports after ACL injuries. To this end, the Sports Medicine Committee of the Chinese Research Hospital Association and the Editorial Board of the Chinese Journal of Trauma jointly formulated the Expert consensus on surgical treatment and rehabilitation for competitive sports athletes returning to sports after anterior cruciate ligament injury ( version 2025), and presented 14 recommendations covering surgical indications, preoperative rehabilitation, surgical timing, surgical strategies and postoperative rehabilitation strategies, aiming to improve the surgical treatment and rehabilitation system for ACL injuries in competitive athletes and facilitate their return to high-level sports performance after injury.

Objective:To investigate the effect of feeder layer cells expressing interleukin(IL)-21 on the amplification of NK cells in vitro.Methods:The K562 cell line with IL-21 expression on its membrane was constructed by electroporation,and co-cultured with NK cells after inactivation.The proliferation of NK cells was observed.The killing function of the amplified NK cells in vitro was evaluated by the lactate dehydrogenase(LDH)and interferon-γ(IFN-y)release assay.A colorectal cancer xenograft model in NOD/SCID mice was established,and a blank control group,a NK cell group and an amplified NK cell group were set up to detect the tumor killing effect of amplified NK cells in vivo.Results:K562 cells expressing IL-21 on the membrane were successfully constructed by electroporation.After co-culturing with K562 cells expressing IL-21 on the membrane for 17 days,the NK cells increased to 700 times,which showed an enhanced amplification ability compared with control group(P＜0.001).In the tumor cell killing experiment in vitro,there was no significant difference in the killing activity on tumor cells between NK cells and amplified NK cells,and there was also no significant difference in mice in vivo.Conclusion:K562 cells expressing IL-21 on the membrane can significantly increase the amplification ability of NK cells in vitro,but do not affect the killing function of NK cells in vitro and in vivo.It can be used for the subsequent large-scale production of NK cells in vitro.

Heart failure(HF)is the end stage of almost all cardiovascular diseases,including coronary heart disease and structural heart disease.For end-stage HF,medications and cardiac assist devices have limited therapeutic effects,and heart transplantation is associated with donor shortage and immune rejection.Alginate hydrogel has the ability to mechanically support and induce cardiac tissue regeneration and repair.In March 2021,we conducted the world's first transcatheter endocardial alginate-hydrogel implantation in patients with end-stage heart failure,and explored the safety and feasibility of the treatment.Given that patients with heart failure who had undergone cardiac resynchronization therapy defibrillator(CRT-D)were excluded from previous studies,this paper is the first to report a case of transcatheter endocardial alginate-hydrogel implantation in a patient with heart failure who did not respond to CRT-D,with a significant reduction in the number of visits to the doctor and a significant improvement in the quality of life during the post-procedure follow-up,which may expand the indications for the use of this technology.

Objective To evaluate the efficacy of extracorporeal membrane oxygenation(ECMO)in patients with reduced left ventricular ejection fraction(LVEF)undergoing transcatheter aortic valve implantation(TAVR).Methods This was a single-center,retrospective study enrolling a total of 30 patients with reduced LVEF undergoing TAVR from January 2020 to January 2024.Of these,12 patients underwent TAVR with ECMO.Baseline clinical characteristics,preprocedural echocardiographic and computed tomographic(CT)measurements,TAVR procedural details,and follow-up data at 60-day and 6-month were collected.Results Among the 30 patients,there were 20 males with an average age of(67.0±10.4)years,an average STS score of(8.2±1.8)points,and an average LVEF of(21.2±5.3)％.This study included 11 AR patients,all of whom were in the group without ECMO implantation,and the difference between the two groups was statistically significant(P=0.027).During the operation,there were 0 cases of circulatory collapse in the ECMO group,and 5 cases(5/18)of circulatory collapse in the non ECMO group.All 5 patients underwent emergency ECMO placement.There were statistically significant differences(P＜0.05)in the comparison of two groups with circulatory collapse and salvage ECMO implantation.The technical success rate of 30 patients was 76.7％(23/30),and the instrument success rate was 60.0％(18/30).Among them,the technical success rate and instrument success rate of the ECMO group were higher than those of the non ECMO group,but the differences were not statistically significant(both P＞0.05).During a 30 day follow-up,there were 0 all-cause deaths in the ECMO group and 9 all-cause deaths(9/18)in the non ECMO group.Among them,7 cases(7/18)died from cardiovascular causes.The differences in all-cause and cardiovascular cause deaths between the two groups were statistically significant(both P＜0.05).During a 6-month follow-up,one patient with ECMO died due to extensive cerebral infarction.The all-cause mortality rate during the 6-month follow-up was 1/12(8.3％),while the all-cause mortality rate without ECMO was 9/18(5.0％).The difference between the two groups was statistically significant(P=0.024).The incidence of stroke with ECMO was 1/12(8.3％),while without ECMO it was 0.There was no statistically significant difference between the two groups(P=0.978).Conclusions In patients with reduced LVEF undergoing TAVR,periprocedural ECMO support does seem to improve patient outcome.

Jumonji domain-containing protein D3(JMJD3)is a 2-oxoglutarate-dependent dioxygenase that specif-ically removes transcriptional repression marks di-and tri-methylated groups from lysine 27 on histone 3(H3K27me2/3).The erasure of these marks leads to the activation of some associated genes,thereby influencing various biological processes,such as development,differentiation,and immune response.However,comprehensive descriptions regarding the relationship between JMJD3 and inflammation are lacking.Here,we provide a comprehensive overview of JMJD3,including its structure,functions,and involvement in inflammatory pathways.In addition,we summarize the evidence supporting JMJD3's role in several inflammatory diseases,as well as the potential therapeutic applications of JMJD3 inhibitors.Additionally,we also discuss the challenges and opportunities associated with investigating the functions of JMJD3 and developing targeted inhibitors and propose feasible solutions to provide valuable insights into the functional exploration and discovery of potential drugs targeting JMJD3 for inflammatory diseases.

Objective: To understand the current status of diagnosis and treatment of chronic lymphocytic leukemia (CLL) /small lymphocytic lymphoma (SLL) among hematologists, oncologists, and lymphoma physicians from hospitals of different levels in China. Methods: This multicenter questionnaire survey was conducted from March 2021 to July 2021 and included 1,000 eligible physicians. A combination of face-to-face interviews and online questionnaire surveys was used. A standardized questionnaire regarding the composition of patients treated for CLL/SLL, disease diagnosis and prognosis evaluation, concomitant diseases, organ function evaluation, treatment selection, and Bruton tyrosine kinase (BTK) inhibitor was used. Results: ①The interviewed physicians stated that the proportion of male patients treated for CLL/SLL is higher than that of females, and the age is mainly concentrated in 61-70 years old. ②Most of the interviewed physicians conducted tests, such as bone marrow biopsies and immunohistochemistry, for patient diagnosis, in addition to the blood test. ③Only 13.7% of the interviewed physicians fully grasped the initial treatment indications recommended by the existing guidelines. ④In terms of cognition of high-risk prognostic factors, physicians' knowledge of unmutated immunoglobulin heavy-chain variable and 11q- is far inferior to that of TP53 mutation and complex karyotype, which are two high-risk prognostic factors, and only 17.1% of the interviewed physicians fully mastered CLL International Prognostic Index scoring system. ⑤Among the first-line treatment strategy, BTK inhibitors are used for different types of patients, and physicians have formed a certain understanding that BTK inhibitors should be preferentially used in patients with high-risk factors and elderly patients, but the actual use of BTK inhibitors in different types of patients is not high (31.6%-46.0%). ⑥BTK inhibitors at a reduced dose in actual clinical treatment were used by 69.0% of the physicians, and 66.8% of the physicians had interrupted the BTK inhibitor for >12 days in actual clinical treatment. The use of BTK inhibitors is reduced or interrupted mainly because of adverse reactions, such as atrial fibrillation, severe bone marrow suppression, hemorrhage, and pulmonary infection, as well as patients' payment capacity and effective disease progression control. ⑦Some differences were found in the perceptions and behaviors of hematologists and oncologists regarding the prognostic assessment of CLL/SLL, the choice of treatment options, the clinical use of BTK inhibitors, etc. Conclusion: At present, a gap remains between the diagnosis and treatment of CLL/SLL among Chinese physicians compared with the recommendations in the guidelines regarding the diagnostic criteria, treatment indications, prognosis assessment, accompanying disease assessment, treatment strategy selection, and rational BTK inhibitor use, especially the proportion of dose reduction or BTK inhibitor discontinuation due to high adverse events.
Female ; Humans ; Male ; Aged ; Middle Aged ; Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy* ; Prognosis ; Lymphoma, B-Cell ; Immunohistochemistry ; Immunoglobulin Heavy Chains/therapeutic use*

Objective: To analyze the immunological characteristics and antibody changes of patients infected with the Omicron BA.1 and evaluate the possibility of secondary infection. Methods: A total of 104 patients infected with Omicron BA.1 in the Jinnan District of Tianjin from January 8 to February 2, 2022, were included in the study. The control group and case group were matched 1∶1 based on age, sex and vaccination status. Serum was collected from the case group and control group at 3, 6 and 9 months after infection. The serum levels of interleukin4 (IL-4), IL-5 and interferon-gamma (IFN-γ), as well as the positive rates of IgG, IgG1 and IgG2, were detected by ELISA. Results: The highest concentration of IFN-γ in the case group at 6 months after infection was 145.4 pg/ml, followed by a decrease in concentration. The concentrations of IL-4 and IL-5 began to decrease at 6 months after infection (all P<0.001). There was no significant difference in the IgG2 positive rate between the case group and the control group at 6 months after BA.1 infection. However, at 9 months, there was a significant decrease compared to the control group (P=0.003). The ratio of IFN-γ/IL4 at 3 months after infection in the case group was lower than that in the control group (P<0.001). There was no significant difference in the ratio between the case group and the control group at 9 months after infection. Conclusion: The cellular immune function has been impaired at 3 months after infection with BA.1, and the specific cellular immune and humoral immune functions decrease significantly after 6 months, and the risk of secondary infection increases.
Adult ; Humans ; Immunity, Humoral ; Coinfection ; Interleukin-4 ; Interleukin-5 ; Immunoglobulin G ; Interferon-gamma