Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Background: and Purpose Live cell-based assays (LCBA) are increasingly used for serological antibody detection due to their ability to preserve antigen conformation, offering moderately higher sensitivity than fixed cell-based assays. However, the clinical necessity of prioritizing LCBA for the detection of aquaporin-4 immunoglobulin G (AQP4-IgG) in neuromyelitis optica spectrum disorder (NMOSD) remains unclear, especially when compared to its established role in diagnosing myelin oligodendrocyte glycoprotein antibody-associated disease. Methods: We compared the performance of live cell-based assays using immunofluorescence (LCBA-IF) and fixed cell-based assays using immunofluorescence (FCBA-IF) in detecting AQP4-IgG in 90 cases of NMOSD meeting 2015 International Panel for Neuromyelitis Optica Diagnosis criteria, alongside 40 controls. Additionally, we further investigated the relationship between AQP4-IgG titers as measured by LCBA-IF and FCBA-IF and clinical parameters in NMOSD patients. Results: Results showed 96.9% agreement between LCBA-IF and FCBA-IF (Cohen’s κ=0.935), with a strong Spearman correlation (0.977, p<0.001). Both methods demonstrated 100% specificity, with LCBA-IF showing slightly higher sensitivity compared to FCBA-IF. Within LCBAIF-tested groups, statistically significant differences in annualized relapse rates were observed across all pairwise comparisons (low-titer vs. moderate-titer, low-titer vs. high-titer, and moderate-titer vs. high-titer; all p<0.050). However, this association reached statistical significance in some FCBA-IF-tested groups. Conclusions Overall, there is a strong concordance between LCBA-IF and FCBA-IF in detecting AQP4-IgG, where LCBA-IF shows slightly higher sensitivity. Furthermore, there is a potential link between elevated AQP4-IgG titers and an increased risk of relapse, and this correlation may appear more pronounced when using LCBA-IF.

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.

Objective To investigate the types of diseases examined by ultrasonography in a certain island clinic,and to summarize the experience of ultrasound medical support in island area.Methods The ultrasound examination results of patients who were admitted to a certain island clinic from January 2017 to August 2022 were reviewed,and the types and characteristics of diseases examined by ultrasound were analyzed.Results A total of 2 043 patients underwent ultrasound examination.There were 76 disease categories and 1 579 diseases.The top five diseases were fatty liver(13.24%),kidney crystals(12.10%),kidney stones(10.70%),gallbladder polyps(6.33%)and ureteral stones with hydronephrosis(6.02%).Ultrasound could predict the pathological types of appendicitis and guide the clinical decision by observing the width of the appendiceal lumen and the layers of the appendiceal wall.Doppler-assessed ureteric jet could be used to determine the renal function of the affected side of ureteral calculi.Conclusion There are wide and varied disease categories in islands.Sonographers should have comprehensive abilities and qualities.This study can provide reference for the follow-up medical support on island area.

Objective To investigate the effect of up-regulating tumor necrosis factor alpha induced protein 3(TNFAIP3)expression on hippocampal neurons in mice with cerebral ischemia-reperfusion.Methods The mice were randomly divided into 6 groups:sham group,sham empty vector group(sham-),sham TNFAIP3 high expression group(sham+),model group,model empty vector group(model-),model TNFAIP3 high expression group(model+).A mouse model of middle cerebral artery occlusion and cerebral ischemia-reperfusion was established using the suture method.After the successful establishment of the model,lentivirus was injected into the hippocampus 24 hours later.Two weeks later,samples were collected and Western blotting was used to detect the expressions of TNFAIP3 and ERK signaling pathway proteins.The changes in ischemic area were observed by 2,3,5-triphenyltetrazolium chloride(TTC)staining;HE staining was used to observe the morphological changes of hippocampal neurons,and ELISA was used to detect the expressions of lipoprotein-associated phospholipase A2(Lp-PLA2)and interleukin(IL)-8.Results The results of Western blotting indicated that the TNFAIP3 expression in the model group decreased significantly compared with the sham group(P＜0.05);Compared with the model group,there was no significant change in TNFAIP3 expression in the model-group(P＞0.05);The TNFAIP3 expression in the model+group increased significantly compared with the model group and model-group(P＜0.05).Compared with the sham group,the results of the sham+group showed that the ischemic area had no significant changes in TTC staining,and there were no significant changes in hippocampal neuronal morphology,and the expressions ERK signaling pathway proteins,Lp-PLA2 and IL-8(P＞0.05);Compared with the sham-and sham+groups,the model group showed an increase in ischemic area,significant damage to hippocampal neurons,a decrease in the number of Nissl bodies,and a significant increase in the expressions of ERK signaling pathway proteins,Lp-PLA2,and IL-8(P＜0.05);Compared to the model-group,the model+group showed a decrease in ischemic area,an increase in the number of neurons in the hippocampus and the number of Nissl bodies,and a significant decrease in the expressions of ERK signaling pathway proteins,Lp-PLA2,and IL-8(P＜0.05).Conclusion Up-regulation of TNFAIP3 may be one of the methods for repairing hippocampal neuronal damage caused by cerebral ischemia reperfusion.

Objective To explore the relevant factors affecting the efficacy of traditional Chinese medicine in treating MG,and to develop and validate a nomogram model,in order to personalize the prediction of the probability of benefits for MG patients after traditional Chinese medicine treatment,further guide clinical physicians in targeted medication,and provide guidance for the traditional Chinese medicine treatment of MG.Method Retrospective analysis of MG patients who visited the Affiliated Hospital of Changchun University of Traditional Chinese Medicine from March 2018 to June 2022,13 clinical factors were selected to evaluate the results.To acquire independent factors,univariate and multivariate Logistic analyses were performed.The area under the receiver operating characteristic curve,Harrell's concordance index,calibration curve,and decision curve analyses were used to evaluate the predictive ability,accuracy,and clinical practicability of the prediction model.Results A total of 204 cases were included,divided into derivation cohort 139 cases and temporal validation cohort 65 cases.Multivariate Logistic regression showed 4 independent predictors affecting effectiveness of traditional Chinese medicine in treating MG,including age at onset,repetitive nerve stimulation positive,oral immunosuppressant and anxiety/depression.AUC values for the model group and validation group were 0.76(95%CI:0.68-0.84)and 0.83(95%CI:0.71-0.95),respectively,and based on calibration curve and decision curve analysis,we concluded that the nomogram showed excellent performance.Conclusion MG patients may experience a decrease in short-term efficacy with age,positive RNS,concomitant emotional abnormalities,or recent history of immunosuppressive therapy.This nomogram effectively predicts the possibility of short-term effective traditional Chinese medicine treatment in MG patients.

Objective:To investigate the predictive value of serum levels of Ninjurin 1(NINJ1),cystatin C(CysC),and D-dimer(D-D)for unfavorable outcomes in patients with acute myocardial infarction(AMI).Methods:A total of 118 AMI patients hospitalized in the Chinese PLA Joint Logistic Support Force 901st Hospital between Feb-ruary 2020 and March 2023 were enrolled.According to prognosis within 6 months after treatment,patients were divided into favorable outcome group and unfavorable outcome group.Serum levels of CysC,D-D and NINJ1 were measured upon admission.Multivariate Logistic regression analysis was conducted to identify the factors influencing unfavorable outcome in AMI patients.Receiver operating characteristic(ROC)curves were used to analyze the pre-dictive value of serum NINJ1,CysC and D-D for the prognosis of AMI patients.A nomogram model for predicting unfavorable outcome in AMI patients was constructed and verified.Results:Compared to patients with favorable outcomes,those with unfavorable outcomes had significantly higher proportions of hypertension,diabetes,number of diseased coronary arteries ≥2,and serum levels of NINJ1,CysC and D-D,as well as a significantly lower pro-portion of Killip class Ⅰ-Ⅱ(P＜0.01 all).Multivariate Logistic regression analysis showed that number of diseased coronary arteries ≥2(OR=3.817,95％CI 1.140～12.779,P=0.030),Killip class Ⅲ-Ⅳ(OR=5.639,95％CI 1.706～18.637,P=0.005),hypertension(OR=4.188,95％CI 1.392～12.600,P=0.011),diabetes(OR=3.480,95％CI 1.148～10.552,P=0.028),and serum levels of NINJ1(OR=1.055,95％CI 1.009～1.103,P=0.018),CysC(OR=75.232,95％CI 5.537～545.908,P=0.003),and D-D(OR=56.163,95％CI 1.610～958.586,P=0.026)were significantly associated with unfavorable outcomes at 6 months in AMI patients.ROC a-nalysis showed that the AUC of serum NINJ1,CysC and D-D combined predicting unfavorable outcomes was 0.801(95％CI 0.718～0.869),which was significantly higher than those of serum NINJ1(0.675,95％CI 0.582～0.758)and D-D(0.676,95％CI 0.583～0.759)alone(Z=2.344,P=0.019;Z=2.173,P=0.030,),but the difference was not significant comparing to CysC alone(Z=1.856,P=0.064).The C-index of the nomogram model predic-ting unfavorable outcomes was 0.973(95％CI 0.967～0.986),and the predicted values of calibration curve were consistent with the actual values,indicating good prediction accuracy.Conclusion:Elevated serum levels of NINJ1,CysC and D-D in AMI patients were significantly associated with unfavorable outcomes.Combined detection of these indicators may accurately predict unfavorable outcomes compared to single detection,and the constructed no-mogram model exhibits good prediction efficacy.

Objective To evaluate the safety and feasibility of percutaneous mitral balloon valvuloplasty with the assistance of arterio-venous circuit.Methods From January 2015 to October 2022,a total 25 patients[19 females,6 males;age(61.60±9.00)years]were included,who were diagnosed with rheumatic heart disease and severe mitral stenosis.A transseptal puncture was performed to establish a femoral arterio-venous circuit,followed by graded dilation with Inoue balloon(diameters:22.00 mm to 28.00 mm).The target was a mitral valve area≥1.50 cm2 with mild or less regurgitation.Results The arterio-venous circuit was established,and mitral balloon valvuloplasty was successfully completed in all 25 patients.Among them,20 patients experienced difficulty with transvalvular crossing using the balloon catheter with conventional methods,16 patients had valvular severe calcification,and 3 patients presented with a left atrial appendage thrombus despite of more than 6-month anticoagulation therapy with warfarin.The mean balloon diameter was(25.00±1.40)mm.The mitral valve area increased from(0.91±0.15)cm2 preoperatively to(1.70±0.14)cm2 postoperatively(P＜0.001).Mean left atrial pressure decreased from(27.00±7.50)mmHg to(16.36±4.07)mmHg(P＜0.001),and mean pulmonary artery pressure decreased from(40.84±13.81)mmHg to(25.00±7.12)mmHg(P＜0.001).All patients showed significant symptom improvement with no complications.Conclusions Arterio-venous circuit for percutaneous mitral balloon valvuloplasty is safe and feasible.This technique can serve as an alternative to standard technique for patients with complex mitral stenosis.

Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells (SSCs). The mechanisms underlying the transition from SSCs to sperm are largely unknown. Most studies utilize gene knockout mice to explain the mechanisms. However, the production of genetically engineered mice is costly and time-consuming. In this study, we presented a convenient research strategy using an RNA interference (RNAi) and testicular transplantation approach. Histone H3 lysine 9 (H3K9) methylation was dynamically regulated during spermatogenesis. As Jumonji domain-containing protein 1A (JMJD1A) and Jumonji domain-containing protein 2C (JMJD2C) demethylases catalyze histone H3 lysine 9 dimethylation (H3K9me2), we firstly analyzed the expression profile of the two demethylases and then investigated their function. Using the convenient research strategy, we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases. These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.
Spermatogenesis/physiology* ; Animals ; Male ; Mice ; Epigenesis, Genetic ; Jumonji Domain-Containing Histone Demethylases/metabolism* ; Histones/metabolism* ; RNA Interference ; Testis/metabolism* ; Methylation ; Mice, Knockout ; Histone Demethylases