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.Effect and mechanism of high-glucose environment on osteoblast function and bone quality in mice
Zhi-Kang GUO ; Xue LI ; Rui WANG ; Xi-Xiu XIE ; Tao-Jin FENG ; Yi LI ; Peng-Bin YIN ; Li-Jun XU ; Li-Xia ZHANG
Medical Journal of Chinese People's Liberation Army 2025;50(10):1306-1314
Objective To explore the effects of different glucose concentrations on the synthesis and secretion of bone collagen in osteoblasts and the impact of diabetes on bone quality in mice.Methods(1)Primary osteoblasts were extracted from the skulls of neonatal mice via collagenase digestion and cultured in four groups under different glucose concentrations:normal glucose(5.5 mmol/L),moderate glucose(11.5 mmol/L),moderate-high glucose(16.5 mmol/L),and high glucose(25 mmol/L).EdU staining was performed to evaluate cell proliferation,while the Transwell assay was used to assess cell migration.Immunofluorescence and Western blotting were performed to detect and quantitatively analyze the content of type Ⅰ collagen(Col-1).Alizarin red S(ARS)staining and alkaline phosphatase(ALP)staining were applied to assess the effects of different glucose concentrations on osteogenic differentiation.(2)Six-week-old male C57BL/6 mice were randomly divided into control group and model group(5 in each group).The model group was fed a high-fat diet for 4 weeks followed by streptozotocin(STZ)injection to establish a diabetic mouse model.The osteogenic differentiation capacity of primary osteoblasts from both groups was assessed.(3)Micro-computed tomography(Micro-CT)was employed to analyze femoral bone mineral density(BMD),bone volume/tissue volume(BV/TV),trabecular number(Tb.N),and trabecular separation(Tb.Sp).Three-point bending test was conducted to evaluate mechanical parameters including maximum load,Young's modulus,fracture energy,and stiffness.RT-qPCR was employed to assess the expression of osteogenic differentiation genes(Alp,Opn,Col1a1,and Lox).Masson staining and Mallory staining were used to evaluate Col-1 content in trabecular bone.Results(1)EdU and Transwell assay results demonstrated that with the gradual increase in glucose concentration,the proliferation and migration abilities of osteoblasts were significantly decreased(P<0.001),and the protein expression levels of Col-1 and lysyl oxidase(LOX)were significantly reduced(P<0.01 or P<0.001).ARS and ALP staining revealed that calcium salt deposition and ALP activity in osteoblasts were significantly decreased with increasing glucose concentration(P<0.05 or P<0.001).(2)Compared with control group,mice in model group exhibited typical"three polies and one weight loss"symptoms(polyuria,polydipsia,polyphagia,and weight loss)of diabetes,and ARS and ALP staining showed a significant reduction in osteoblasts(P<0.001).(3)Micro-CT and three-point bending test results indicated that,compared with control group,mice in model group showed microarchitectural deterioration of bone,decreased Tb.N,increased Tb.Sp,and significantly reduced maximum load,Young's modulus,fracture energy,and stiffness(P<0.05).RT-qPCR results showed that the relative mRNA expression levels of osteogenic differentiation genes(Alp,Opn,Col1a1,and Lox)were significantly decreased in model group compared with control group(P<0.01 or P<0.001).Masson and Mallory staining indicated a significant reduction in collagen content in model group compared with control group(P<0.01).Conclusions High-glucose environment inhibits osteoblast proliferation,differentiation,and migration.Diabetic mice exhibit reduced bone quality and increased bone fragility,potentially mediated by decreased lysyl oxidase and collagen levels.
4.Construction and evaluation of a nomogram model for predicting the risk of hypertension in Dongxiang adults based on obesity and muscle mass indices
Xiu-Lin YANG ; Peng CHENG ; Bin MA ; Wei-Hong MA ; Xiang-Jun HAI
Acta Anatomica Sinica 2025;56(3):336-341
Objective To analyze the relationship between obesity indicators,muscle mass indices and hypertension in Dongxiang adults,and establish and evaluate a Nomogram model based on these indicators used to predict the risk of hypertension in this population.Methods A total of 1209 Dongxiang adults from Linxia Prefecture,Gansu Province were selected,11 obesity indicators and 5 muscle mass indicators,including neck circumference(NC),waist-to-hip ratio(WHR),BMI,ponderal index(PI),conicity index(CI),a body shape index(ABSI),body roundness index(BRI),abdominal volume index(AVI),hip index(HI),body adiposity index(BAI),and the ratio of limb fat mass to body weight(LFWR),appendicular skeletal muscle mass(ASM),appendicular skeletal muscle mass index(ASMI),appendicular skeletal muscle mass to BMI ratio(ASMBMI),skeletal muscle index(SMI),and trunk muscle mass to body weight ratio(TMWR)were measured.Logistic regression analysis was used to explore the relationship between each indicator and hypertension.Nomogram prediction model was constructed and validated by using R language.Results Among Dongxiang males,the NC,BMI,PI,WHR,CI,AVI,BRI,BAI,ASM,ASMI,and LFWR were lower in the normal and high-normal blood pressure groups compared to the hypertensive group,while SMI,ASMBMI,and TMWR were higher.Among females,similar trends were observed,with lower NC,BMI,PI,WHR,CI,AVI,BRI,BAI,and LFWR in the normal blood pressure and high-normal blood pressure groups compared to the hypertensive group,but SMI,ASMBMI,and TMWR higher than the hypertensive group(P<0.05).Results of multivariate Logistic regression analysis indicated that age,NC,and WHR were risk factors for hypertension in Dongxiang adults,while was protective factor(P<0.05).The area under curve(AUC)of the Nomogram model constructed based on these factors was 0.796,and the Bootstrap internal validation C-index was 0.7957,indicating good calibration of the model.Conclusion The Nomogram model constructed based on obesity and muscle mass indicators has good predictive efficiency for predicting the risk of hypertension in Dongxiang adults.
5.Construction and evaluation of intestinal mucosal epithelial-myofibroblast co-culture model
Peng-Xin YU ; Ming-Qi WANG ; Li-Na GUO ; Yu YU ; Xiu-Li WANG
Acta Anatomica Sinica 2025;56(4):438-443
Objective To construct a three-dimensional bionic model of intestinal mucosal structure in vitro.Methods Using fibroin protein with villous-crypt structure as scaffold and Caco-2 and HT29-MTX-E12 as seed cells,the intestinal mucosal epithelial-myofibroblast co-culture model was constructed by three-dimensional co-culture with myofibroblasts in vitro.The growth,activity,histological characteristics and expression of functional genes of model cells were investigated through the detection of cell signature proteins and genes.Results 1.An intestinal mucosal epithelial-myofibroblast co-culture model was successfully constructed with good cell activity.2.Mucous secretion increased and muc2 gene expression was up-regulated in the co-culture model.Conclusion The co-culture of intestinal mucosal epithelial-myofibroblasts with villous-crypt structure can promote the functional differentiation of intestinal epithelial cells and better simulate the structure and function of intestinal mucosa in vivo.
6.Relative dimensions of the first metatarsals within 12 extant primates
Tao LU ; Peng JING ; Meng-Nan ZHANG ; Xiu-Li HUO ; Bao-Pu DU ; Yan GAO
Acta Anatomica Sinica 2025;56(6):730-737
Objective To investigate the size variation in the first metatarsal of extant primates.Methods In this study,we analyzed 135 first metatarsal specimens across 12 primate genera,quantifying eight linear measurements,articular surface areas,mid-shaft cross-sectional area,total surface area,volume,and derived indices.Multivariate patterns were assessed through mean-based correspondence analysis and principal component analysis(PCA).Results Eulemur,Otolemur,Cebus,and Perodicticus exhibited a relatively high metatarsal surface-area-to-volume ratio.Perodicticus additionally showed a low articular facet index.Propithecus,Colobus,and Macaca displayed lower values for metatarsal shaft robusticity,the ratio of shaft cross-sectional area to base articular surface area,and the proximal articular facet index.Nasalis possessed a relatively high articular facet index.Pongo,Pan,Gorilla,and Homo sapiens were characterized by higher metatarsal shaft robusticity and a lower metatarsal surface-area-to-volume ratio.Principal component analysis revealed that the 12 extant primate genera could be broadly divided into two groups.Group 1 comprised Pongo,Pan,Gorilla and H.sapiens,although H.sapiens formed a distinct cluster relative to the extant great apes.Group 2 included Eulemur,Otolemur,Perodicticus,Propithecus,Cebus,Colobus,Macaca and Nasalis.Conclusion The relative sizedistribution of the first metatarsal provides some reference value for classifying extant primates.However,it demonstrates no clear correlations with specific locomotor patterns or foot grasping ability.
7.Screening of Illicit Oxyphenisatin Substances in Weight-Loss Dietary Supplements by High Performance Liquid Chromatography-in-Source-Fragmentation-Quadrupole Time-of-Flight Mass Spectrometry
Hong-Fei SHI ; Ke-Yu LIU ; Bo-Peng XU ; Cheng-Xin XU ; Xiu-Qi ZHOU ; Yi-Fei ZHOU ; Ming-Xin GUO
Chinese Journal of Analytical Chemistry 2025;53(9):1576-1585,后插1-后插9,封3
By summarizing the mass spectrometric fragmentation patterns of oxyphenisatin substances,an analytical method was established for screening of illegally added oxyphenisatin compounds in weight-loss health foods using high performance liquid chromatography-in-source-fragmentation-quadrupole time-of-flight mass spectrometry(HPLC-ISF-QTOF-MS),along with a quantitative method for 11 kinds of oxyphenisatin compounds.Based on the developed screening method,an oxyphenisatin derivative was discovered in the reference standards,which was tentatively identified as 4-(3-(4-hydroxyphenyl)-2-oxoindolin-3-yl)phenyl acetate and confirmed by MS/MS analysis.The results showed that all 11 kinds of oxyphenisatin compounds had correlation coefficients greater than 0.9971,with limits of detection(LODs)ranging from 0.12 to 0.68 μg/L and limits of quantification(LOQ)from 0.21 to 2.29 μg/L.The LODs for 11 kinds of characteristic ions ranged from 0.45 to 9.11 μg/kg.At spiking levels of 25,50 and 100 μg/kg,the recoveries ranged from 78.9%to 117.3%.The instrumental precision,intra-day method precision and inter-day method precision were 0.23%?1.70%,0.7%?2.4%,and 1.1%?3.3%,respectively.The developed targeted and non-targeted detection method demonstrated high sensitivity,strong stability,rapid analysis,and an expanded screening range for oxyphenisatin substances,and provided robust technical support for regulatory authorities in combating illegal adulteration.
8.Quality evaluation of Commelina communis medicinal materials from different origins based on content of four alkaloid components combined with chemometrics.
Bi-Ru FU ; Wei-Jie ZHUO ; Xuan-Xiu HUANG ; Peng-Cong LU ; Xin HE ; Rui-Feng JI
China Journal of Chinese Materia Medica 2025;50(9):2422-2431
This study employs ultra-performance liquid chromatography(UPLC) to analyze the differences in alkaloid content of Commelina communis from various geographical origins, exploring its feasibility as a quality evaluation indicator. A total of 57 batches of C. communis samples from 23 provinces, autonomous regions, and municipalities in China were selected. The MicroPulite HSS T3(2.1 mm×50 mm, 1.8 μm)column was used with a mobile phase of acetonitrile-0.2% phosphoric acid aqueous solution(20∶80), detection wavelength at 254 nm, and a flow rate of 0.3 mL·min~(-1) to measure the content of 1-deoxynojirimycin(DNJ) and deoxymannojirimycin(DMJ). The MicroPulite XP tC_(18)(2.1 mm×100 mm, 1.7 μm)column was employed with a mobile phase of acetonitrile-0.2% phosphoric acid aqueous solution(4∶96), detection wavelength at 254 nm, and a flow rate of 0.4 mL·min~(-1) to measure the content of norharmine(NHM) and harmanme(HM). Chemometric methods were applied to study the relationships and differences among the 57 batches of C. communis. Significant differences in alkaloid content were observed among C. communis from different regions, with the average total content decreasing in the order of North China, Northeast China, Northwest China, East China, Southwest China, Central China, and South China. Cluster analysis(CA) and principal component analysis(PCA) further revealed the quality differences of C. communis from various origins, and partial least squares discriminant analysis(PLS-DA) identified DNJ as a marker compound to distinguish the quality differences between different geographical sources of C. communis. It is recommended that the content limit of DNJ be set at no less than 0.055 9%, providing a reference for the quality evaluation and clinical application of C. communis medicinal materials.
Alkaloids/analysis*
;
Drugs, Chinese Herbal/chemistry*
;
China
;
Chromatography, High Pressure Liquid
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Chemometrics/methods*
;
Quality Control
9.Key technology and equipment development status of first-aid robotics
Zhen-bao WANG ; Zi-jian WANG ; Xin-xi XU ; Xin LIU ; Tao CHENG ; Pei-peng LIU ; Xiu-guo ZHAO ; Chen SU
Chinese Medical Equipment Journal 2025;46(3):96-114
The development status of the key technologies of first-aid robotics was introduced in autonomous system,embo-died intelligence,digital twins,large artificial intelligence model and autonomous unmanned medical treatment.The present situation in first-aid robotics equipment was reviewed for first-aid diagnosis,treatment,assistance and transportation.The development trends of the key technology and equipment of first-aid robotics were analyzed.It was pointed out the involve-ment of big model-based embodied intelligence technology and digital twins technology in first aid might provide new pers-pectives for the application and advancement of specialized first-aid robotics.[Chinese Medical Equipment Journal,2025,46(3):96-114]
10.Value of DCE-MRI quantitative parameters in differential diagnosis of brain metastases from non-small cell lung cancer
Rui-peng LIANG ; Yong-long LI ; Hao-tian WANG ; Dan SU ; Xiu-fu ZHANG ; Jun ZHOU
Chinese Medical Equipment Journal 2025;46(5):54-59
Objective To evaluate the value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)in differentiating histopathological types of brain metastases from non-small cell lung cancer(NSCLC).Methods Sixty-eight patients with brain metastases confirmed by pathology were collected,including 47 lung adenocarcinoma patients divided into a lung adenocarcinoma group and 21 lung squamous cell carcinoma patients into a lung squamous cell carcinoma group.The two groups were compared in terms of the DCE-MRI derived parameters including volume transfer constant(Ktrans),extra vascular extracellular volume fraction(Ve)and plasma volume fraction(Vp);ROC curves were used to assess the diagnostic efficacy of different quantitative parameters for the pathologic types of brain metastases from lung adenocarcinoma group or lung squamous cell carcinoma.SPSS 22.0 software was used for statistical analysis.Results The lung adenocarcinoma group had the values of Ktrans,Ve,Vp and Ve+Vp higher than those of the lung squamous cell carcinoma group,with the differences being statistically significant(all P<0.05).ROC curve analysis results showed that Ktrans,Vp and Ve had high differential diagnosis values for the pathologic types of brain metastases from lung adenocarcinoma group or lung squamous cell carcinoma,with the AUC being 1.000,0.998 and 0.875,the optimal Youden index being 0.183 min-1,0.039 and 0.270,the sensitivity being 100.00%,100.00%and 80.56%and the specificity being 100.00%,97.06%and 80.88%,respectively.Conclusion The quantitative parameters of DCE-MRI gain advantages in the differential diagnosis of NSCLC brain metastases,and provide references for the diagnosis and treatment of brain metastases of lung cancer.[Chinese Medical Equipment Journal,2025,46(5):54-59]

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