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.Effects of honey-processed Astragalus on energy metabolism and polarization of RAW264.7 cells
Hong-chang LI ; Ke PEI ; Wang-yang XIE ; Xiang-long MENG ; Zi-han YU ; Wen-ling LI ; Hao CAI
Acta Pharmaceutica Sinica 2025;60(2):459-470
In this study, RAW264.7 cells were employed to investigate the effects of honey-processed
4.Yubi-Wakka Test for Sarcopenia Screening: Influence of Abdominal Obesity on Diagnostic Performance
Melissa Rose Berlin PIODENA-APORTADERA ; Sabrina LAU ; Cai Ning TAN ; Justin CHEW ; Jun Pei LIM ; Noor Hafizah ISMAIL ; Yew Yoong DING ; Wee Shiong LIM
Annals of Geriatric Medicine and Research 2025;29(1):138-141
5.Effects of galectin-3 on oxidative damage and expression of inflammatory fac-tors in retinal pigment epithelial cells induced by high glucose
Pei LIU ; Yu CAI ; Decheng WANG ; Shanshan HAN
Recent Advances in Ophthalmology 2025;45(4):269-275
Objective To investigate the effects of galectin-3(Gal3)on autophagy in high glucose-induced human telomerase reverse transcriptase-immortalized retinal pigment epithelial(hTERT-RPE)cells.Methods The hTERT-RPE cells cultured in vitro were randomly divided into a normal group(group C),a high glucose group(group HG),a high glu-cose+si-NC group(group HG+si-NC)and a high glucose+si-Gal3 group(group HG+si-Gal3).Reverse transcrip-tion polymerase chain reaction(RT-PCR)was used to detect the relative mRNA expression levels of Gal3,intercellular ad-hesion molecule(ICAM)-1,interleukin(IL)-6 and tumor necrosis factor(TNF)-α in hTERT-RPE cells of each group.The expression levels of IL-1 and IL-6 in the supernatant of hTERT-RPE cells were measured by enzyme-linked immunosorbent assay(ELISA).The expression level of reactive oxygen species(ROS),the activity of superoxide dismutase(SOD)and the content of malondialdehyde(MDA)in hTERT-RPE cells were analyzed by dichlorofluorescin diacetate(DCFH-DA)staining,the colorimetric method and the microplate method,respectively.The protein expression levels of Gal3,the ratio of microtubule associated protein 1 light chain 3(LC3)type Ⅱ to type Ⅰ(LC3 Ⅱ/LC3 Ⅰ),Beclin 1,and autophagy-associat-ed 5(ATG5)and 7(ATG7)in hTERT-RPE cells from each group were detected by Western blot analysis.After the hTERT-RPE cells in each group were transfected with double fluorescent mRFP-GFP-LC3 plasmids alone and with RFP-LAMP1 and GFP-LC3 plasmids jointly,the changes of autophagy flow in hTERT-RPE cells were detected by laser confocal microscopy.Results Compared with the group C,the group HG showed an increase in the expression of Gal3,IL-1,IL-6,TNF-α,ICAM-1,P62,ROS and MDA content(all P<0.05).However,the expression of LC3 Ⅱ/LC3 Ⅰ,Beclin1,ATG7,ATG5,the SOD activity,and the number of red(autolysosomes)and yellow fluorescence spots(autophagosomes)of the double fluo-rescent mRFP-GFP-LC3 plasmid were all lower in the group HG than those in the group C(all P<0.05).There was no sig-nificant difference in the number of yellow fluorescent spots(autolysosomes)co-located by RFP-LAMP1 and GFP-LC3 plas-mids between groups C and HG(P>0.05).There were no significant differences in the expression levels of the above-mentioned indexes in hTERT-RPE cells between groups HG and HG+si-NC(all P>0.05).The expression levels of Gal3,IL-1,IL-6,TNF-α,ICAM-1,P62,ROS and MDA content in hTERT-RPE cells of the group HG+si-Gal3 were lower than those of the group HG+si-NC(all P<0.05).Compared with those in the group HG+si-NC,the expression levels of LC3 Ⅱ/LC3 Ⅰ,Beclin1,ATG7,ATG5,SOD activity,and the number of red and yellow fluorescent spots of the double fluo-rescent mRFP-GFP-LC3 plasmid were increased in the group HG+si-Gal3(all P<0.05).There was no significant differ-ence in the number of yellow fluorescent spots co-located by RFP-LAMP1 and GFP-LC3 plasmids between groups HG+si-GaL3 and HG+si-NC(P>0.05).Conclusion Gal3 is significantly elevated in hTERT-RPE cells induced by high glu-cose,resulting in impaired autophagy flow.It produces a direct regulatory effect on the formation of autophagosomes,and plays a highly active role in oxidative damage and expression of inflammatory factors in hTERT-RPE cells induced by high glucose.
6.Development of an evaluation indicator system for access to cancer screening services: a Delphi study
Xin WANG ; Ayan MAO ; Xinyi ZHOU ; Pei DONG ; Yanjie LI ; Senyao CAI ; Yujie WU ; Huiyao HUANG ; Guoxiang LIU ; Wanghong XU ; Jiangmei QIN ; Wanqing CHEN ; Jufang SHI
Chinese Journal of Epidemiology 2025;46(2):307-315
Objective:To present an evaluation indicator system for access to cancer screening services.Methods:The evaluation indicator pool was constructed through a scoping review. The theoretical framework was constructed based on the multi-source indicators, and the qualitative expert consultation method was employed to form the initial version of the three-level evaluation indicator system. Delphi expert consultation method was conducted in two rounds to evaluate the relevance, importance, and availability of the proposed evaluation indicator system. The expert positive coefficient, authority coefficient, coordination degree of expert opinions, and concentration of expert opinions were subjected to analysis. Subsequently, the three-level evaluation indicator system for access to cancer screening services was adjusted and determined based on the boundary value method and the open opinions of experts. Finally, the combination weight method was employed to determine the weight.Results:The initial version of the indicator system comprised 3 primary (first-level) indicators, 11 secondary (second-level) indicators, and 46 tertiary (third-level) indicators. Delphi expert consultation was conducted for the initial version, and 17 experts ultimately completed it, exhibiting a positive coefficient of 100% and an authority coefficient of 0.87. In comparison to the initial round of consultation, Kendall's W coefficient ranges (0.15-0.43, all P<0.05) of relevance, importance, and availability scores for each tertiary indicator in the second round exhibited an improvement. The analysis of the importance dimension indicates that expert opinions are also more concentrated, as evidenced by an increase of 8.5% and 7.0% in the proportion of the tertiary indicators with an arithmetic mean above 8 and a full mark ratio above 0.5, respectively. The final evaluation indicator system comprises three primary indicators, with the weights of structure evaluation, process evaluation, and outcome evaluation being 0.338, 0.378, and 0.285, respectively. It also comprises 11 secondary indicators and 45 tertiary indicators. Conclusions:The evaluation indicator system developed in this article can be an effective evaluation tool for quantitative comparison of access to cancer screening services across different populations, cancer types, and before and after intervention. Furthermore, it is recommended that the system undergo continuous optimization concerning its application.
7.Competency of infectious disease epidemic response and influencing factors in task force members in county (district) Centers for Disease Control and Prevention in China
Wenjing LI ; Jian CAI ; Mingzhai WANG ; Zhuo JIN ; Lijie ZHANG ; Yingxin PEI ; Huihui LIU ; Huilai MA
Chinese Journal of Epidemiology 2025;46(5):796-802
Objective:To understand the current status of epidemiological investigation task force construction and the performance of infectious disease epidemic response in county (district) Centers for Disease Control and Prevention (CDCs) in China, analyze the influencing factors and provide scientific evidence to improve the construction of grassroot epidemiological investigation task force.Methods:A survey was conducted in epidemiological investigation staff in county (district) CDCs in 31 provinces (autonomous regions/municipalities) and Xinjiang Production and Construction Corps in China. A self-designed questionnaire was used to collect information based on the epidemiological dynamic data collection platform of China CDC. A descriptive epidemiological analysis was conducted, and multiple linear regression models were used to identify the factors associated with the performance of infectious disease epidemic response.Results:A total of 24 934 epidemiological investigation task force members from 2 897 county (district) CDCs were surveyed in the study. In the epidemiological investigation task force, women, those with bachelor's degree and public health workers accounted for 62.46%, 71.36%, and 49.05% respectively. Up to 91.72% of the task force members had participated in field epidemic response. The average score of awareness of epidemic investigation procedures was 60.00, while the average score of key skill proficiency in the investigation was 42.22. The epidemic response performance showed correlations with area, gender, age, education level, major, and field epidemiology training programs, those who had received longer training showed higher competency scores (all P<0.001). Conclusions:Progress has been made in the construction of epidemiological investigation task force in grass-root CDCs in China, but further improvements are needed, especially in the knowledge awareness and investigation skills of the task force. Field epidemiology training demonstrated substantial impact on the improvement of epidemic response performance, indicating that it is necessary to further strengthen the training in grassroot public health workers for the better response to infectious disease epidemics.
8.Effects of Yiqi Juanbi Formula on chondrocyte pyroptosis in collagen-induced arthritic rats via NF-κB/NLRP3/Caspase-1 signaling pathway
Xin-yu CUI ; Hao-lin LI ; Wei-qing LI ; Hui-qin KANG ; Wei-gang CHENG ; Pei-xin HE ; Cai-hong YANG ; Ping CHEN ; Hai-dong WANG
Chinese Traditional Patent Medicine 2025;47(9):2880-2887
AIM To investigate the effects of Yiqi Juanbi Formula on chondrocyte pyroptosis in rat models of collagen-induced arthritis(CIA).METHODS Fifty rats were subcutaneously injected at the tail base with an emulsion containing equal volumes of bovine type Ⅱ collagen and incomplete Freund's adjuvant(IFA)to establish the CIA models.These rats were then randomly assigned to the model group,the methotrexate group(0.35 mg/kg),and the low-dose,medium-dose,and high-dose Yiqi Juanbi Formula groups(9.4,18.7,37.4 g/kg),in contrast to the ten intact rats serving in the normal control group.Following four weeks of intragastric administration,the rats had their general conditions observed;their joint swelling and arthritis indices measured;their ankle joint pathology assessed by HE staining;their serum levels of IL-1β,IL-18 and TNF-ɑ detected by ELISA;their mRNA expressions of NLRP3,Caspase-1,GSDMD,IL-1β,IL-18 and TNF-ɑ in ankle cartilage quantified by RT-qPCR;their protein expressions of NF-κB,NLRP3 and Caspase-1 in ankle cartilage analyzed by Western blot;and their NLRP3 and GSDMD positive expressions in ankle cartilage examined by immunohistochemistry.RESULTS Compared to the control group,the model group showed significantly increased joint swelling and arthritis indices(P<0.01);elevated serum levels of IL-1 β,IL-18 and TNF-ɑ(P<0.01);pathological changes including cartilage surface defects,reduced cell count,altered cellular morphology,irregular cell arrangement,and significant inflammatory cell infiltration in synovial tissue;upregulated mRNA expressions of NF-κB,NLRP3,Caspase-1,GSDMD,IL-1β,IL-18 and TNF-ɑ(P<0.01)and increased protein expressions of NF-κB,NLRP3 and Caspase-1(P<0.01)in ankle cartilage;enhanced positive expressions of NLRP3 and GSDMD in ankle cartilage(P<0.01).Compared to the model group,the groups intervened with methotrexate or medium-or high-dose Yiqi Juanbi Formula exhibited reduced joint swelling and arthritis indices(P<0.01);alleviated pathological damage in ankle joints;decreased serum levels of IL-1β,IL-18 and TNF-ɑ(P<0.01);downregulated mRNA expressions of NF-κB,NLRP3,Caspase-1,GSDMD,IL-1β,IL-18 and TNF-ɑ(P<0.05,P<0.01),and reduced protein expressions of NF-κB,NLRP3 and Caspase-1(P<0.05,P<0.01)in ankle cartilage;and diminished positive expressions of NLRP3 and GSDMD in ankle cartilage(P<0.01).CONCLUSION Yiqi Juanbi Formula alleviates inflammation in CIA rats,potentially by inhibiting the activation of the NF-κB/NLRP3/Caspase-1 signaling pathway,thereby suppressing chondrocyte pyroptosis.
9.Development of an evaluation indicator system for access to cancer screening services: a Delphi study
Xin WANG ; Ayan MAO ; Xinyi ZHOU ; Pei DONG ; Yanjie LI ; Senyao CAI ; Yujie WU ; Huiyao HUANG ; Guoxiang LIU ; Wanghong XU ; Jiangmei QIN ; Wanqing CHEN ; Jufang SHI
Chinese Journal of Epidemiology 2025;46(2):307-315
Objective:To present an evaluation indicator system for access to cancer screening services.Methods:The evaluation indicator pool was constructed through a scoping review. The theoretical framework was constructed based on the multi-source indicators, and the qualitative expert consultation method was employed to form the initial version of the three-level evaluation indicator system. Delphi expert consultation method was conducted in two rounds to evaluate the relevance, importance, and availability of the proposed evaluation indicator system. The expert positive coefficient, authority coefficient, coordination degree of expert opinions, and concentration of expert opinions were subjected to analysis. Subsequently, the three-level evaluation indicator system for access to cancer screening services was adjusted and determined based on the boundary value method and the open opinions of experts. Finally, the combination weight method was employed to determine the weight.Results:The initial version of the indicator system comprised 3 primary (first-level) indicators, 11 secondary (second-level) indicators, and 46 tertiary (third-level) indicators. Delphi expert consultation was conducted for the initial version, and 17 experts ultimately completed it, exhibiting a positive coefficient of 100% and an authority coefficient of 0.87. In comparison to the initial round of consultation, Kendall's W coefficient ranges (0.15-0.43, all P<0.05) of relevance, importance, and availability scores for each tertiary indicator in the second round exhibited an improvement. The analysis of the importance dimension indicates that expert opinions are also more concentrated, as evidenced by an increase of 8.5% and 7.0% in the proportion of the tertiary indicators with an arithmetic mean above 8 and a full mark ratio above 0.5, respectively. The final evaluation indicator system comprises three primary indicators, with the weights of structure evaluation, process evaluation, and outcome evaluation being 0.338, 0.378, and 0.285, respectively. It also comprises 11 secondary indicators and 45 tertiary indicators. Conclusions:The evaluation indicator system developed in this article can be an effective evaluation tool for quantitative comparison of access to cancer screening services across different populations, cancer types, and before and after intervention. Furthermore, it is recommended that the system undergo continuous optimization concerning its application.
10.Competency of infectious disease epidemic response and influencing factors in task force members in county (district) Centers for Disease Control and Prevention in China
Wenjing LI ; Jian CAI ; Mingzhai WANG ; Zhuo JIN ; Lijie ZHANG ; Yingxin PEI ; Huihui LIU ; Huilai MA
Chinese Journal of Epidemiology 2025;46(5):796-802
Objective:To understand the current status of epidemiological investigation task force construction and the performance of infectious disease epidemic response in county (district) Centers for Disease Control and Prevention (CDCs) in China, analyze the influencing factors and provide scientific evidence to improve the construction of grassroot epidemiological investigation task force.Methods:A survey was conducted in epidemiological investigation staff in county (district) CDCs in 31 provinces (autonomous regions/municipalities) and Xinjiang Production and Construction Corps in China. A self-designed questionnaire was used to collect information based on the epidemiological dynamic data collection platform of China CDC. A descriptive epidemiological analysis was conducted, and multiple linear regression models were used to identify the factors associated with the performance of infectious disease epidemic response.Results:A total of 24 934 epidemiological investigation task force members from 2 897 county (district) CDCs were surveyed in the study. In the epidemiological investigation task force, women, those with bachelor's degree and public health workers accounted for 62.46%, 71.36%, and 49.05% respectively. Up to 91.72% of the task force members had participated in field epidemic response. The average score of awareness of epidemic investigation procedures was 60.00, while the average score of key skill proficiency in the investigation was 42.22. The epidemic response performance showed correlations with area, gender, age, education level, major, and field epidemiology training programs, those who had received longer training showed higher competency scores (all P<0.001). Conclusions:Progress has been made in the construction of epidemiological investigation task force in grass-root CDCs in China, but further improvements are needed, especially in the knowledge awareness and investigation skills of the task force. Field epidemiology training demonstrated substantial impact on the improvement of epidemic response performance, indicating that it is necessary to further strengthen the training in grassroot public health workers for the better response to infectious disease epidemics.

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