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.

OBJECTIVE To investigate the effects of Chuangling Ye(CLY)on diabetic foot ulcer(DFU)model mice based on the nuclear factor erythroid 2-related factor 2(Nrf2)/solute carrier family 7 member 11(SLC7A11)/glutathione peroxidase 4(GPX4)pathway and explore its potential mechanism.METHODS In animal experiments,streptozotocin(STZ)-induced diabetic mice with full-thickness skin defects were divided into control,model,positive control(recombinant human epidermal growth factor,rhEGF),and CLY low-and high-dose groups(n=10).After 14 days of intervention,wound healing rate was measured.Serum inflammatory factors(IL-6,TNF-α,IL-1β)were detected by ELISA,while oxidative stress markers(SOD,MDA,GSH)and tissue ferrous iron(Fe2+)levels were measured by colorimetric assays.Mitochondrial ultrastructure was observed via transmission electron microscopy(TEM).Nrf2,SLC7A11,and GPX4 expression in wound tissues were analyzed by qPCR and Western blot.In cell experiments,a high glucose(HG)-induced ferroptosis model in human umbilical vein endothelial cells(HUVECs)was established and divided into control,HG,CLY,and CLY combined with pathway inhibitors(ML385,Erastin,RSL3)groups.CCK-8 was used to detect cell via-bility,FerroOrange was used to detect Fe2+content,DCFH-DA and C11-BODIPY 581/591 probes were used to detect intracellular ROS and lipid ROS content,and Western blot was used to detect the expression of proteins such as Nrf2/SLC7A11/GPX4.RESULTS Animal experiments showed that compared with the model group,the wound healing rate in the low-and high-dose CLY groups was significantly improved(P<0.01);the serum IL-6,IL-1β,and TNF-α levels were significantly decreased(P<0.01);the MDA con-tent was significantly reduced(P<0.01),and the SOD activity and GSH content were significantly restored(P<0.05).Colorimetric a-nalysis showed that the low-and high-dose CLY significantly reduced the abnormally elevated Fe2+levels in DFU wounds(P<0.05,P<0.001).Electron microscopy showed that the mitochondrial cristae structure was improved in the low-and high-dose groups.qPCR showed that high-dose CLY upregulated the expression levels of Rno-Nfe2l2(Nrf2),Rno-Slc7a11,Rno-Gpx4,and Rno-Acsl4 mR-NA,and inhibited the expression level of Rno-Acsl4 mRNA(P<0.001).Western blot results showed that CLY upregulated the expres-sion of Nrf2,SLC7A11,GPX4,and FTH1 in DFU wound tissues(P<0.01),while downregulated the level of ACSL4(P<0.01).Cell experiments showed that treatment with CLY increased the survival rate of high glucose-stimulated HUVECs(P<0.001).However,the protective effect of CLY was significantly inhibited after the addition of ML385,Erastin,or RSL3(P<0.01).Treatment with CLY significantly decreased the Fe2+content(P<0.001),which was reversed by ML385,Erastin,or RSL3.The levels of ROS and lipid ROS were also significantly reduced(P<0.001),while the addition of ML385,Erastin,or RSL3 partially weakened the antioxidant effect of CLY.Western blot results showed that CLY significantly upregulated the expression of Nrf2、SLC7A11 and GPX4(P<0.001)and downregulated the expression of 4-HNE and COX2(P<0.01),and ML385,Erastin,or RSL3 could reverse this protective effect.CONCLUSION CLY promotes DFU healing by activating the Nrf2/SLC7A11/GPX4 pathway to inhibit ferroptosis,mitigate oxidative stress,and suppress inflammation,providing a novel therapeutic target for DFU.

Aim To establish a simple and practical method for visualizing neurovascular coupling in the mouse barrel cortex in vivo.Methods Male C57BL/6J mice received stereotaxic in-jections of pAAV-hSyn-jGCaMP7s-WPRE into the barrel cortex to monitor neuronal activity.Three weeks post-injection,a crani-al window was implanted,and TRITC-Dextran 155 ku was ad-ministered intravenously to visualize the vasculature and blood flow dynamics.A custom-built whisker stimulator was used to e-voke controlled neuronal excitation.Two-photon microscopy was employed to monitor neuronal and vascular responses to whisker stimulation in real-time.Results Neuronal calcium signals and plasma signals were clearly observed using two-photon microsco-py.Whisker stimulation led to a significant increase in neuronal calcium signals in the barrel cortex,indicating effective neuronal activation.This neuronal excitation was accompanied by a syn-chronous increase in blood vessel diameter,blood flow velocity and overall blood flow.Conclusions This study successfully establishes a three-dimensional visualization framework(spatial,temporal,and functional)for in vivo visualization of neurovascu-lar coupling in the mouse barrel cortex,which provides a useful tool for investigating the pathophysiological mechanisms of neuro-vascular dysfunction and evaluating the efficacy of potential ther-apies.

Methodological quality assessment is a pivotal link between primary studies and reliable evidence-based practice,and an essential pathway for operationalizing the core principles of the Guide on Methodological Standards in Pharmacoepidemiology(2nd edition).A prevalent challenge in practice,however,is the conflation of appraising methodological robustness(risk of bias assessment)with verifying reporting transparency(adherence to reporting guidelines).This paper systematically addresses this fundamental challenge,beginning with a clear distinction between the essence and boundaries of these two concepts.On this basis,the article provides a comprehensive review of mainstream quality assessment tools,covering the methodological features and evolutionary trajectory of numerous instruments for interventional(e.g.,RoB 2,ROBINS-I),observational(e.g.,NOS,the JBI/SIGN/NIH series),secondary(e.g.,AMSTAR 2),and other specific types of studies such as health economic evaluations.Furthermore,a complete case study is used to illustrate the practical application of the ROBINS-I tool.The paper's central thesis advocates for an"appraisal-informed design"philosophy,urging a conceptual shift from the retrospective critique of existing literature to the prospective quality control of new research by internalizing appraisal standards as design principles,while also exploring the emerging paradigm of artificial intelligence in assisting assessment.This paper provides a comprehensive methodological reference for researchers and practitioners to prudently select appropriate assessment tools and to conduct rigorous critical appraisals of pharmacoepidemiological evidence.

Aim To explore the mechanism of Yangxin decoction in the treatment of chronic heart failure(CHF)based on network pharmacology and animal ex-periments.Methods The database was used to screen Yangxin decoction,a network of"drug-compo-nent-disease-target"was established,and the obtained targets were enriched and analyzed.The CHF model of rats was replicated by abdominal aortic ligation.After the administration,the general condition,body weight and heart weight of the rats were observed,and the he-modynamic changes,echocardiography indicators and left ventricular mass index were measured.HE staining was used to observe the morphological changes of myo-cardial tissue.Serum IL-1 β,IL-18,TNF-α and BNP were detected by ELISA.The expressions of NLRP3,caspase-1,ASC and NF-κB p65 proteinswere detected by Western blot.Results Enrichment analysis showed that the potential regulatory pathways of Yangx-in decoction in the treatment of CHF involved NOD-like signaling pathway,NF-κB signaling pathway,etc.The results of animal experiments showed that the body weight,left ventricular diastolic diameter and left ven-tricular systolic diameter of the rats in the administra-tion group decreased(P＜0.05),the left ventricular mass index,ejection fraction and short axis narrowing rate increased(P＜0.05),the pathological morphology of myocardial tissue was reduced,and the levels of IL-1 β,IL-18,TNF-α,BNP,NLRP3,caspase-1,ASC and NF-κB p65 decreased(P＜0.05).Conclusions The mechanism of Yangxin decoction in the treatment of CHF rats may be related to inhibiting the activation of NLRP3 inflammasome signaling pathway and reduc-ing the inflammatory response.

Objective To design a high altitude adaptive oxygen generator for the crews to alleviate their high altitude reaction in high altitude environment and meet their requirements for oxygen supply.Methods A high altitude adaptive oxygen generator based on the mature pressure swing adsorption oxygen production method was designed with the key technologies of discharge capacity compensation of air compression pump and airway fusion of molecular sieve tower,which had the components of molecular sieve tower,air compression pump,controller,cooling fan,cooler,solenoid valve,regulator,flow meter and etc.Trials were carried out at the simulated altitude and field plateau environment so as to verify the high altitude adaptive performance of the oxygen generator developed.Results The trial results showed the oxygen generator met the desired objectives and the requirements for oxygen volume fraction in GJB 2799-1996 General specification for medical oxygen generator using molecular sieve method.Conclusion The oxygen generartor provides oxygen supply effectively for vehicle operators in plateau environments or the ones rushing into the plateau.[Chinese Medical Equipment Journal,2025,46(4):29-34]

Aim To investigate the protective effect of Gualou Guizhi granules(GLGZG)on neuronal injury induced by LPS-activated microglia based on Notch signaling pathway.Methods LPS-activated microglia were co-cultured with neurons to construct neuron inju-ry models,and the cells were divided into the control group,model group,Notch inhibitor(DAPT)group,GLGZG(50,100,200 mg·L-1)group,DAPT+100 mg·L-1GLGZG group.After intervention,the activity of HT22 cells was detected by CCK-8 method,and rel-ative mRNA expression was detected by real-time PCR.The relative protein expression was detected by Western blot.Results Compared with the model group,after GLGZG intervention,the cell activity was significantly improved,GLGZG decreased IL-6,IL-12,Bax,Notch 1,caspase-3,Delta-1,NICD,RBPSUH,HES1 expression,and increased Bcl-2 expression(P＜0.05).Compared with the model group,the NICD,RBPSUH and HES1 mRNA and protein expressions significantly decreased after DAPT treatment(P＜0.05),and there was no superposition effect with GLG-ZG.Conclusion GLGZG may play a neuroprotective role by inhibiting inflammatory factors and apoptosis,and inhibiting Notch signaling pathway.

Aim To investigate the interventional effects of polysaccharides from Dicliptera chinensis(L.)Juss.(DCP)on acute liver failure(ALF)in-duced by lipopolysaccharide(LPS)combined with D-galactosamine(D-GalN)in mice,and on LPS-induced inflammatory responses in RAW264.7 cells,based on the TLR-4/MyD88/NF-κB signaling pathway.Meth-ods Mice were randomly divided into the control,model,silymarin,DCP low,medium,and high dose groups,and toxicity test groups.After 10 consecutive days of treatment,ALF models were established by in-jecting mice with LPS+D-GalN.Additionally,an in-flammatory response model was established by stimula-ting RAW264.7 cells with LPS.Results Biochemical assays showed that compared with the model group,the medium-and high-dose DCP groups exhibited de-creased serum ALT,AST,ALP,TBIL,and γ-GT activi-ties(P＜0.05),reduced levels of ROS,MPO and MDA in liver(P＜0.05),increased activities of SOD,GSH-Px,CAT,and elevated T-AOC levels(P＜0.05).ELISA revealed lower levels of ICAM-1,VCAM-1,IL-6,IL-1β,and TNF-α in liver(P＜0.05).HE staining indicated reduced inflammatory cell infiltration and improved hepatocyte necrosis in liv-er after DCP administration.The use of DCP alone showed no significant organ toxicity.qRT-PCR and Western blot results indicated that DCP inhibited the expression of key factors in TLR-4/MyD88/NF-κB sig-naling pathway(P＜0.05).Cell validation experi-ments also confirmed that this pathway was inhibited by DCP.Conclusion DCP alleviates ALF primarily by inhibiting oxidative stress and blocking the activation of the TLR-4/MyD88/NF-κB signaling pathway.

OBJECTIVE To investigate the effects of Chuangling Ye(CLY)on diabetic foot ulcer(DFU)model mice based on the nuclear factor erythroid 2-related factor 2(Nrf2)/solute carrier family 7 member 11(SLC7A11)/glutathione peroxidase 4(GPX4)pathway and explore its potential mechanism.METHODS In animal experiments,streptozotocin(STZ)-induced diabetic mice with full-thickness skin defects were divided into control,model,positive control(recombinant human epidermal growth factor,rhEGF),and CLY low-and high-dose groups(n=10).After 14 days of intervention,wound healing rate was measured.Serum inflammatory factors(IL-6,TNF-α,IL-1β)were detected by ELISA,while oxidative stress markers(SOD,MDA,GSH)and tissue ferrous iron(Fe2+)levels were measured by colorimetric assays.Mitochondrial ultrastructure was observed via transmission electron microscopy(TEM).Nrf2,SLC7A11,and GPX4 expression in wound tissues were analyzed by qPCR and Western blot.In cell experiments,a high glucose(HG)-induced ferroptosis model in human umbilical vein endothelial cells(HUVECs)was established and divided into control,HG,CLY,and CLY combined with pathway inhibitors(ML385,Erastin,RSL3)groups.CCK-8 was used to detect cell via-bility,FerroOrange was used to detect Fe2+content,DCFH-DA and C11-BODIPY 581/591 probes were used to detect intracellular ROS and lipid ROS content,and Western blot was used to detect the expression of proteins such as Nrf2/SLC7A11/GPX4.RESULTS Animal experiments showed that compared with the model group,the wound healing rate in the low-and high-dose CLY groups was significantly improved(P<0.01);the serum IL-6,IL-1β,and TNF-α levels were significantly decreased(P<0.01);the MDA con-tent was significantly reduced(P<0.01),and the SOD activity and GSH content were significantly restored(P<0.05).Colorimetric a-nalysis showed that the low-and high-dose CLY significantly reduced the abnormally elevated Fe2+levels in DFU wounds(P<0.05,P<0.001).Electron microscopy showed that the mitochondrial cristae structure was improved in the low-and high-dose groups.qPCR showed that high-dose CLY upregulated the expression levels of Rno-Nfe2l2(Nrf2),Rno-Slc7a11,Rno-Gpx4,and Rno-Acsl4 mR-NA,and inhibited the expression level of Rno-Acsl4 mRNA(P<0.001).Western blot results showed that CLY upregulated the expres-sion of Nrf2,SLC7A11,GPX4,and FTH1 in DFU wound tissues(P<0.01),while downregulated the level of ACSL4(P<0.01).Cell experiments showed that treatment with CLY increased the survival rate of high glucose-stimulated HUVECs(P<0.001).However,the protective effect of CLY was significantly inhibited after the addition of ML385,Erastin,or RSL3(P<0.01).Treatment with CLY significantly decreased the Fe2+content(P<0.001),which was reversed by ML385,Erastin,or RSL3.The levels of ROS and lipid ROS were also significantly reduced(P<0.001),while the addition of ML385,Erastin,or RSL3 partially weakened the antioxidant effect of CLY.Western blot results showed that CLY significantly upregulated the expression of Nrf2、SLC7A11 and GPX4(P<0.001)and downregulated the expression of 4-HNE and COX2(P<0.01),and ML385,Erastin,or RSL3 could reverse this protective effect.CONCLUSION CLY promotes DFU healing by activating the Nrf2/SLC7A11/GPX4 pathway to inhibit ferroptosis,mitigate oxidative stress,and suppress inflammation,providing a novel therapeutic target for DFU.