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.

Exercise-induced muscle damage (EIMD) is a frequent form of skeletal muscle microdamage that occurs after high-intensity, prolonged, or unaccustomed exercise, especially exercise dominated by eccentric contractions. It is commonly characterized by delayed-onset muscle soreness, transient loss of muscle strength, local inflammation, structural disruption of myofibers, and delayed functional recovery. Although mild EIMD may serve as a stimulus for training adaptation, excessive or insufficiently recovered muscle damage can impair exercise performance, disturb training continuity, and reduce participation in physical activity. Therefore, clarifying the molecular mechanisms that underlie the initiation, amplification, and resolution of EIMD is important for optimizing athletic training, improving post-exercise recovery, and guiding evidence-based public fitness practice. Necroptosis is a regulated form of programmed cell death mediated primarily by the receptor-interacting protein kinase (RIPK) 1/RIPK3/mixed lineage kinase domain-like protein (MLKL) signaling axis. Recent studies have shown that necroptosis is closely involved in tissue injury, sterile inflammation, and repair remodeling. However, whether necroptosis acts as an initiating driver, a secondary damage amplifier, or an adaptive signal required for repair after EIMD remains unclear. This review aimed to summarize the potential role of necroptosis in EIMD and to establish a mechanistic framework linking regulated cell death, inflammatory amplification, immune regulation, and skeletal muscle repair. Relevant studies concerning EIMD, necroptosis, RIPK1/RIPK3/MLKL signaling, damage-associated molecular patterns (DAMPs), inflammatory responses, immune cell recruitment, extracellular matrix remodeling, and muscle regeneration were reviewed and integrated. On this basis, the possible temporal and functional involvement of necroptosis in different phases of EIMD was analyzed. The main evidence summarized in this review suggests that EIMD is not merely a consequence of primary mechanical disruption. Instead, it develops through a dynamic sequence that includes sarcolemmal instability, calcium overload, mitochondrial dysfunction, oxidative stress, inflammatory mediator production, immune cell infiltration, necrotic tissue clearance, and regeneration-associated remodeling. Necroptosis may participate in this process through at least two interconnected mechanisms. First, in the early or progressive phase of EIMD, activation of the RIPK1/RIPK3/MLKL signaling axis may promote MLKL phosphorylation and plasma membrane permeabilization, leading to the release of DAMPs such as high-mobility group box 1, ATP, mitochondrial DNA, and other intracellular components. These signals may activate innate immune pathways, amplify inflammatory cytokine production, and enhance the recruitment of neutrophils and macrophages, thereby aggravating secondary inflammation and extending muscle fiber injury. Second, during the resolution and repair phases, necroptosis-related signaling may also contribute indirectly to the formation of a regenerative microenvironment. By influencing the clearance of necrotic debris, the recruitment and phenotypic transition of immune cells, and the remodeling of extracellular matrix components, necroptosis may affect satellite cell activation, myogenic repair, and the eventual structural and functional recovery of injured skeletal muscle. Thus, the biological effect of necroptosis in EIMD may be context dependent rather than uniformly harmful. Its outcome may depend on exercise intensity, the extent of tissue damage, the timing of pathway activation, the involved cell types, inflammatory status, training background, age, and metabolic condition. In conclusion, necroptosis may represent an important molecular link between skeletal muscle injury, sterile inflammation, and tissue repair after damaging exercise. It may exert a dual role in EIMD by amplifying secondary damage while also contributing to repair coordination under appropriate temporal and microenvironmental conditions. Future studies should determine the activation pattern of RIPK1/RIPK3/MLKL signaling after different exercise protocols, identify the major cell populations undergoing necroptosis in injured skeletal muscle, and examine whether targeted modulation of necroptosis can reduce excessive inflammation without impairing necessary regenerative responses. This review provides a theoretical basis for understanding the pathogenesis of EIMD and for developing targeted strategies to improve skeletal muscle recovery after exercise-induced injury.

We reported the clinical manifestations,radiographic characteristics and prognosis of 1 case with Mycolicibacterium wolinskyi pulmonary disease,and provided a comprehensive literature review on this disease.Using"M.wolinskyi"OR"Mycobacterium wolinskyi"OR"Mycolicibacterium wolinskyi"as search term in PubMed database,CNKI and Wanfang database up to August 26 2023,40 reports were retrieved.32 cases from the literature and 1 case of our institution were used for review.A 59-year-old female presented intermittent hemoptysis since 2015.She was diagnosed with tuberculosis and clinical symptoms continued after anti-tuberculosis treatment.After multiple cultures of mycobacterium sputum and species identification in our hospital,M.wolinskyi was finally identified.She was diagnosed with M.Wolinski pulmonary disease according to clinical symptoms,computed tomography findings as well as bacteriological examinations.Combination therapy with Azithromycin,Moxifloxacin hydrochloride and Amikacin were administered based on antimicrobial susceptibility testing.Mycobacterium sputum culture became negative after 1 month treatment and kept negative,and the patient continued this combination therapy for 12 months after first culture negative.M.wolinskyi disease is exceedingly rare in medical institutions,and clinical symptoms are different depending on different location.Most cases were infected with skin,soft tissue or bone tissue infection after trauma or surgery,and a few cases were bloodstream infection.Most patients could have a good prognosis after proper treatment.M.wolinskyi disease is rare and clinically atypical,which may lead to long-term misdiagnosis.With the increase of aged or immunosuppressed population,the diagnosis and treatment of these rare non-tuberculous mycobacterial infections deserve more attention.

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 assess the impact of urban-rural health insurance integration on the non-agricultural employment of rural labor in China.Methods:Using CHFS data(2011-2019)and a DID model,this study analyzed the impact on non-agricultural employment probability and quality(wage income,job stability)and examined the effect of different integration models.Results:The integration of urban and rural health insurance significantly increases the probability and quality of non-agricultural employment among rural labor.This effect operates through three key mechanisms:easing household liquidity constraints,improving health-related human capital,and expanding job search scope.Moreover,the"unified urban-rural tier"model proves more effective than the"one-system-multi-tiers"model in promoting non-agricultural employment and enhancing job quality.Conclusion:The integration positively contributes to improving rural labor allocation efficiency and mobilizing surplus rural labor capacity.Policy recommendations include accelerating the adoption of the"unified urban-rural tier"model and further refining the urban-rural resident health insurance system.

Aim To evaluate the ameliorative effects of different ratios of Renshen-Huangjing(RH) on SPS-induced PTSD-like behaviors in mice,and to investi-gate the action mechanism using bioinformatics analysis and experimental studies.Methods The aqueous ex-tract was extracted in four ratios of RH in a total weight of 60 g,i.e.1∶0(RH1),2∶1(RH2),1∶2(RH3),and 0∶1(RH4).The extraction rates of Rg1,Rb1,and polysaccharides from different ratios of RH were then detected using UPLC-UV method.The SPS model was established,and RH1,RH2,RH3 and RH4(400 mg·kg-1)were administered by intragas-tric gavage for 14 day,followed by behavioral tests to e-valuate the PTSD-like behaviors.The serum CORT,IL-1β and IL-10 were determined by ELISA.The possible targets of action were analyzed using bioinformatics.The expression levels of Calpain-1,PSD95,BDNF and GluN2B in the hippocampus were detected by Western blot.Results The SPS model induced PTSD-like be-haviors in mice.Serum levels of CORT and IL-1β in-creased and level of IL-10 decreased in SPS model.After treatment with different ratios of RHs,RH2 showed the best therapeutic effect,which was manifes-ted in the suppression of PTSD-like behaviors,the re-duction of CORT and IL-1β levels,and the promotion of IL-10 levels;160 overlapping targets might explain the therapeutic effects of RH on PTSD,and these tar-gets were enriched in inhibiting synaptic damage,exer-ting antioxidant properties and suppressing neuroin-flammation,respectively.RH2 prevented the SPS-in-duced decrease in the expression of Calpain-1,PSD95,BDNF and the elevation of GluN2B.Molecular docking showed strong binding of Rg1 and Rb1 to Calpain-1,PSD95,and BDNF,respectively.Conclusions The a-queous extract of RH in a 2∶1 ratio can more effec-tively prevent SPS-induced PTSD-like behaviors,and its effect may be related to targets such as Calpain-1,PSD95,BDNF and GluN2B.

Aim To investigate the key targets and mechanisms of diabetic gastroparesis(DGP)by in-tegrating network pharmacology and molecular docking technology with animal experiments,and to specifically focus on exploring the effects of hedysarum polybotrys polysaccharide(HPS)on DGP through animal experi-mentation to validate its potential as a treatment for di-abetic gastroparesis.Methods The chemical constit-uents of HPS were analyzed,and the active chemical components of Radix Astragali were identified using the TCMSP database.The Swisstarget database was utilized to screen for HPS active ingredient targets,while DGP-related targets were identified from disease databases such as TTD,GeneCards,Drugbank,and DisGeNET.The STRING database was used to construct the PPI network,and Cytoscape 3.10.1 software was employed for network topology analysis and selection of key tar-gets.Subsequently,a compound-target-pathway net-work diagram was constructed.Key targets underwent GO function(biological function,molecular function,and cellular function)and KEGG pathway enrichment analysis using the Metascape database.Molecular doc-king was performed using Pymol 2.5 and AutoDock software.DGP rat model was established to observe the histopathological changes in small intestine after eight weeks of HPS intervention through HE staining.Addi-tionally,Western blot was conducted to detect the ex-pression of AGEs,RAGE,and NF-κB in eggs.The re-sults revealed a total of 302 key targets.Results A total of 302 key targets which were further analyzed for gene GO function and KEGG pathway enrichment.CUL3,YWHAZ,and NTRK1 were predicted as the key targets with critical pathways including the AGE-RAGE signaling pathway in diabetic complications,viral carci-nogenesis,hepatitis B,and alcoholism signaling path-way among others.Furthermore,in vivo experiments confirmed that HPS could improve small intestine histo-pathology in DGP rats,resulting in significant protective effects on this organ.It also reduced the expression of AGEs,RAGE,and NF-κB protein,hence achieving its purpose of treating DGP.Conclusion HPS has the characteristics of multi-component,multi-target and multi-pathway action,which may affect the regulatory role of AGE-RAGE signaling pathway on DGP,and provide new ideas for the subsequent clinical improve-ment of DGP.

Objective:To analyze the influencing factors for choice of secondary disciplines in eight-year medical students majoring in clinical medicine based on the self-determination theory.Methods:Fourteen eight-year students majoring in clinical medicine in 2018 and 2019 from an affiliated medical school of Peking University Health Science Center were selected to conduct semi-structured interviews using purposive sampling and descriptive phenomenological study methods. The thematic framework method was used to analyze the interview data and refine the theme.Results:Through the analysis of interview data, a total of 3 dimensions were obtained, including 6 first-level topics and 19 second-level topics: ①autonomy dimension (interest factor and value factor); ②dimension of competence (personal trait factor and subject requirement factor); and ③belonging dimension (department factor and mentor factor).Conclusions:The sense of autonomy based on interests and values, the sense of competence matched with personal ability and the characteristics of the discipline, and the sense of belonging brought by the atmosphere of the department and the mentor are important factors influencing the choice of secondary disciplines in eight-year medical students. Teachers and teaching managers should pay attention to the cultivation of students' interests and value guidance, early contact with secondary disciplines, provision of competency training, and promotion of good interaction between students and department tutors, so as to enhance students' sense of belonging and optimize the training model of eight-year excellent doctors.