1.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
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.
2.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
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.
3.Guide on Methodological Standards in Pharmacoepidemiology(2nd edition)and their series interpretation(10):an overview and case study of quality assessment tools
Qingyong ZHENG ; Caihua XU ; Yongjia ZHOU ; Xiao TANG ; Mengjun ZHANG ; Jinzhi QI ; Ming LIU ; Ya GAO ; Feng SUN ; Jinhui TIAN
Chinese Journal of Pharmacoepidemiology 2025;34(10):1113-1126
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.
4.Mechanism of Yangxin Decoction in treating chronic heart failure based on network pharmacology and experimental verification
Jing-jing CHEN ; Ya-bin ZHOU ; Yue HE ; Chao HUANG ; Wen-feng ZHANG
Chinese Pharmacological Bulletin 2025;41(5):942-950
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.
5.Design and performance verification of high altitude adaptive oxygen generator
Bo WANG ; Xiao-feng LIU ; Wen-jia LIU ; Yi LI ; Ya-nan WU ; Shu-jie CUI ; Wei ZHANG
Chinese Medical Equipment Journal 2025;46(4):29-34
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]
6.The protective effect of Gualou Guizhi granules on neuronal injury induced by LPS-activated microglia based on Notch signaling pathway
Xue-zhen LI ; Xiao-xue ZOU ; Wen-ting CHEN ; Yi FENG ; Ya-nan LI ; Yu-qin ZHANG ; Li-hong NAN
Chinese Pharmacological Bulletin 2025;41(4):781-786
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.
7.Mechanism of Yangxin Decoction in treating chronic heart failure based on network pharmacology and experimental verification
Jing-jing CHEN ; Ya-bin ZHOU ; Yue HE ; Chao HUANG ; Wen-feng ZHANG
Chinese Pharmacological Bulletin 2025;41(5):942-950
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.
8.Design and performance verification of high altitude adaptive oxygen generator
Bo WANG ; Xiao-feng LIU ; Wen-jia LIU ; Yi LI ; Ya-nan WU ; Shu-jie CUI ; Wei ZHANG
Chinese Medical Equipment Journal 2025;46(4):29-34
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]
9.The protective effect of Gualou Guizhi granules on neuronal injury induced by LPS-activated microglia based on Notch signaling pathway
Xue-zhen LI ; Xiao-xue ZOU ; Wen-ting CHEN ; Yi FENG ; Ya-nan LI ; Yu-qin ZHANG ; Li-hong NAN
Chinese Pharmacological Bulletin 2025;41(4):781-786
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.
10.Quantitative analysis of motion of cardiac substructures in deep inspiratory breath holding radiotherapy for left breast cancer
Zhao-hui TANG ; Zhe ZHANG ; Wei-bin MAO ; Bo HUANG ; Jun-feng AI ; Chao-fan ZHU ; Zhi-chao XIE ; Ya-jie LIU
Chinese Medical Equipment Journal 2025;46(3):54-58
Objective To quantify the volume and movement of cardiac substructures by using coronary computed tomography angiography(CCTA)to provide guidance for the design of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.Methods Totally 18 female patients who received conventional chest plain scan and CCTA were selected to simulate the design process of radiotherapy plan for left breast cancer patients with internal mammary lymph nodes.Retrospective reconstruction of CCTA data was performed for each patient,with 10 phase images(with an interval of 10%)within a R-R cardiac cycle(10%-100%)to simulate the true range of motion of the heart.The heart,left atrium(LA),left ventricle(LV),right atrium(RA),right ventricle(RV),left anterior descending artery(LAD),left circumflex coronary artery(LCX)and right coronary artery(RCA)were contoured at each phase.The distances from the centroid position to the average position of LAD,LCX and RCA were measured at each phase in the superior-inferior(SI),anterior-posterior(AP)and left-right(LR).The average volume and range of volume changes of LA,LV,RA,RV and heart were analyzed within a cardiac cycle.The expansion margins of planning organs at risk volume(PRV)were calculated.SPSS 19.0 software was used for statistical analysis.Results The following average absolute displacements were found in SI,AP and LR coordinates:(1.8±0.7)mm,(1.2±0.5)mm and(1.5±0.5)mm for LAD,respectively;(2.1±0.7)mm,(1.5±0.6)mm and(1.9±0.7)mm for LCX,respectively;(1.6±0.5)mm,(2.2±0.9)mm and(2.2±0.8)mm for RCA,respectively.The volume changes of LA,LV,RA,RV and heart within a cardiac cycle ranged from 34.3 to 63.9 cm3,122.1 to 154.3 cm3,29.3 to 53.6 cm3,57.2 to 94.3 cm3 and 480.1 to 515.4 cm3,respectively.The theoretical expansion margins of LAD,LCX and RCA in all the three directions were within 2 mm.Conclusion The ranges of movement and volume changes of cardiac substructure are quantitati-vely displayed,and references are provided for the planning of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.[Chinese Medical Equipment Journal,2025,46(3):54-58]

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