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.Analysis of soil-borne nematode infection status among rural communities in Yubei, Chongqing
Dan JIANG ; Yong-dong HAO ; Sen-ping YANG ; Xiao-yuan SU ; Hua-jun BAI ; Bo LYU ; Ya-ling RAN ; He-yi GUAN ; Ling HU
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):85-89
Objective To analyze the infection status and epidemic trends of soil-borne nematode infections in Yubei, Chongqing City, in 2010,2021, and 2022. Methods The local populations from four survey sites of four towns in 2010 and five sites of five towns in 2021 and 2022 were surveyed regarding their basic information using a unified form. Fecal samples of the participants were collected and tested for soil-borne nematode infections using the modified Kato-Katz thick smear method. Results In 2010, 2 049 participants were surveyed, followed by 1 000 participants in 2021 and 2022. The overall prevalence of parasitic infections declined significantly from 3.86% to 0.20%. In 2010, soil-transmitted nematode included hookworms(3.81%) and roundworms(0.29%). In 2021, the infection rates of roundworms and hookworms were 1.70% and 0.10% respectively. Notably, only Ascaris was identified in 2022(0.20%). The≥60 age group consistently exhibited the highest infection rates across all surveys, followed by the 40-59 age group. The infection rates of males in the three surveys were 3.31%,1.92%, and 0.20% respectively, and those of females were 4.37%, 1.46%, and 0.20% respectively. There was no statistically significant difference in the infection rates between males and females. Educational attainment was inversely associated with infection; in 2010, the highest prevalence was observed among those with primary education or below, whereas in 2021, illiterate or semi-literate individuals showed the highest susceptibility. The occupational distribution of infections in 2010 indicated that retirees (8.33%), farmers(4.86%), and homemakers or unemployed individuals(3.45%)were the most affected. However, in 2021 and 2022, farmers emerged as the predominant occupational group with soil-transmitted nematode infections. Conclusions The infection rate of soil-borne nematodes showed a decreasing trend in Yubei, and the infection species changed from hookworms in 2010 to Ascaris in 2022. Farmers, the elderly, and people with low education levels should continue to be the focus of preventive and control efforts.
4.A quality improvement study on improving the follow-up rate of preterm infants after discharge.
He-Sheng CHANG ; Xue YANG ; Jun JU ; Wen-Ya XU ; Di WU ; Xiao-Man WAN ; Zheng-Hong LI
Chinese Journal of Contemporary Pediatrics 2025;27(2):148-154
OBJECTIVES:
To explore the measures to improve the follow-up rate of preterm infants after discharge, and to evaluate the effectiveness of these measures using quality improvement methodology.
METHODS:
The follow-up status of preterm infants discharged from March to May 2017 was used as the baseline before quality improvement, and a specific quality improvement goal for the follow-up rate was proposed. The Pareto chart was used to analyze the causes of follow-up failure, and a key driver diagram was constructed based on the links involved in improving follow-up rate. The causes of failure were analyzed to determine the key links and intervention measures for quality improvement, and the follow-up rate was monitored weekly using a control chart until the quality improvement goal was achieved.
RESULTS:
The follow-up rate of preterm infants after discharge was 57.92% (117/202) at baseline before quality improvement, and the quality improvement goal was set to increase the follow-up rate of preterm infants from baseline to more than 80% within 12 months. The Pareto chart analysis showed that the main causes of follow-up failure were deficiencies in follow-up file management and irregular follow-up times (33.70%, 31/92), insufficient follow-up education and poor communication (25.00%, 23/92), and the inability to meet the diverse needs of parents (18.48%, 17/92). Based on the key links for quality improvement and the main causes of follow-up failure, the following intervention measures were adopted: (1) strengthen follow-up publicity and education; (2) build a follow-up team; and (3) establish a follow-up platform and system. The control chart indicated that with the implementation of the above intervention measures, the weekly follow-up rate increased to 74.09% (306/413) in July 2017 and 83.09% (511/615) in December 2017, finally achieving the quality improvement goal. During the COVID-19 pandemic, the follow-up rate of preterm infants fluctuated between 23.54% (460/1 954) and 70.97% (1 931/2 721), and subsequently, it returned to pre-pandemic levels starting in February 2023.
CONCLUSIONS
The application of quality improvement methodology can help to formulate intervention measures based on the main causes of follow-up failure, thereby improving the follow-up rate of preterm infants after discharge. This quality improvement method is feasible and practical and thus holds promise for clinical application.
Humans
;
Quality Improvement
;
Infant, Premature
;
Infant, Newborn
;
Patient Discharge
;
Follow-Up Studies
;
Female
;
Male
5.Association of Body Mass Index with All-Cause Mortality and Cause-Specific Mortality in Rural China: 10-Year Follow-up of a Population-Based Multicenter Prospective Study.
Juan Juan HUANG ; Yuan Zhi DI ; Ling Yu SHEN ; Jian Guo LIANG ; Jiang DU ; Xue Fang CAO ; Wei Tao DUAN ; Ai Wei HE ; Jun LIANG ; Li Mei ZHU ; Zi Sen LIU ; Fang LIU ; Shu Min YANG ; Zu Hui XU ; Cheng CHEN ; Bin ZHANG ; Jiao Xia YAN ; Yan Chun LIANG ; Rong LIU ; Tao ZHU ; Hong Zhi LI ; Fei SHEN ; Bo Xuan FENG ; Yi Jun HE ; Zi Han LI ; Ya Qi ZHAO ; Tong Lei GUO ; Li Qiong BAI ; Wei LU ; Qi JIN ; Lei GAO ; He Nan XIN
Biomedical and Environmental Sciences 2025;38(10):1179-1193
OBJECTIVE:
This study aimed to explore the association between body mass index (BMI) and mortality based on the 10-year population-based multicenter prospective study.
METHODS:
A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality. Stratified analyses were performed based on the individual characteristics of the participants.
RESULTS:
Overall, 19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died. The underweight (< 18.5 kg/m 2) presented an increase in all-cause mortality (adjusted hazards ratio [ aHR] = 2.00, 95% confidence interval [ CI]: 1.66-2.41), while overweight (≥ 24.0 to < 28.0 kg/m 2) and obesity (≥ 28.0 kg/m 2) presented a decrease with an aHR of 0.61 (95% CI: 0.52-0.73) and 0.51 (95% CI: 0.37-0.70), respectively. Overweight ( aHR = 0.76, 95% CI: 0.67-0.86) and mild obesity ( aHR = 0.72, 95% CI: 0.59-0.87) had a positive impact on mortality in people older than 60 years. All-cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m 2 ( aHR = 0.95, 95% CI: 0.92-0.98) and increased slightly above that value, indicating a U-shaped association. The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses.
CONCLUSION
This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years. Therefore, it is essential to consider age differences when formulating health and weight management strategies.
Humans
;
Body Mass Index
;
China/epidemiology*
;
Male
;
Female
;
Middle Aged
;
Prospective Studies
;
Rural Population/statistics & numerical data*
;
Aged
;
Follow-Up Studies
;
Adult
;
Mortality
;
Cause of Death
;
Obesity/mortality*
;
Overweight/mortality*
6.Sex development disorder with discordant chromosome karyotype and gene detection:a case report and literature review
Yan-Lin REN ; Ya-Li LI ; Kun LI ; Fan ZHANG ; Li-Min RONG ; Xiao-Ping YU ; Jun GU ; Yan-Hua KANG ; Ying HE
Medical Journal of Chinese People's Liberation Army 2025;50(1):50-56
Objective To report the diagnosis,treatment,and verification process of a patient with sex development disorder whose chromosomal karyotype and genetic test results are inconsistent,and conduct a literature review to improve the understanding of the mosaic status of sexual development disorders.Methods A 14-year-old patient presented with primary amenorrhea on April 3,2020,at the First Affiliated Hospital of Hebei North University,exhibiting female sexual characteristics.The patient underwent ultrasonic/magnetic resonance imaging of gonads,assessment of gonadal axis function,chromosomal karyotype,and molecular genetic testing,as well as pelvic exploration,malignant gonads resection,and hormone replacement therapy,resulting in drug-induced menstruation.During the diagnosis and treatment,it was found that the patient's chromosomal karyotype analysis was inconsistent with the molecular genetic test results.Subsequently,samples from the three germ layer cells were taken,and fluorescence in situ hybridization(FISH)was used to detect the sex chromosomes in each germ layer cell.XY probes were used to label the gonadal pathological sections to explore the distribution differences of the Y chromosome in the gonads,and changes in anti-Müllerian hormone(AMH)levels before and after surgery were compared.Databases such as Wanfang and PubMed were searched to summarize relevant cohort study literature and understand the current status of research on this disease.Results The patient's body exhibited a significant differences between the 45,X and 46,XY cell lines in different germ layers and within the same layer tissues.The proportion of 45,X in buccal mucosal cells derived from the ectoderm was 30%(6/20),in peripheral blood lymphocytes derived from the mesoderm was 9.7%(11/114),and in bladder shed cells derived from endoderm was 20.4%(22/108).The gonadal pathological sections labeled with XY probes indicated a mosaic state with a reduced Y-chromosome;where the epididymal structure area had a 45,X cell line mosaic of 50.0%,and the malignant area had a normal"Y"content.After gonadal resection,AMH levels significantly dropped from 7.28 pmol/L to<0.07 pmol/L.Literature review revealed that patients with 45,X/46,XY have a complex phenotype spectrum,most with features of Turner syndrome,and female phenotypes are at risk of gonadal tumors.Conclusions In the diagnosis of difficult cases of sex development disorders,when performing peripheral blood karyotype testing,the number of counted cells and analyzed cells should be increased as much as possible,and multi-germ layer cell sampling should be performed.Gonads with a high"Y"mosaic rate are more prone to malignancy in the abdominal cavity.Detecting AMH levels can distinguish cryptorchidism and anorchidism in sexual development disorders with Y chromosomes.
7.Screening and Preliminary Validation of Multiple Myeloma Specific Proteins
Shan ZHAO ; Hui-Hui LIU ; Xiao-Ying YANG ; Wei-Wei XIE ; Chao XUE ; Xiao-Ya HE ; Jin WANG ; Yu-Jun DONG
Journal of Experimental Hematology 2025;33(1):127-132
Objective:To screen novel diagnostic marker or therapeutic target for multiple myeloma(MM).Methods:Sel1L,SPAG4,KCNN3 and PARM1 were identified by bioinformatics method based on GEO database as high expression genes in MM.Their RNA and protein expression levels in bone marrow mononuclear cells from myeloma cell lines U266,NCI-H929,MM.1s,RPMI8226 and leukemia cell line THP1,as well as 31 MM patients were evaluated by RT-PCR and Western blot,respectively.Meanwhile,5 samples of bone marrow from healthy donors for allogeneic hematopoietic stem cell transplantation were employed as controls.Results:Compared with leukemia cell line THP1,the expression levels of KCNN3,PARM1 and Sel1L mRNA were significantly increased in myeloma cell lines U266,NCI-H929 and MM.1s,while PARM1 was further increased in myeloma cell lines 8226.Western blot showed that the 4 genes were all expressed in the 4 myeloma cell lines.Compared with healthy controls,the expression levels of Sel1L,SPAG4,KCNN3 and PARM1 mRNA were significantly higher in MM patients(all P<0.05).Western blot showed that the 4 genes were all expressed in MM patients,and the protein expression level of Sel1L and KCNN3 were significantly different compared with healthy donors(all P<0.01).Conclusion:Sel1L,SPAG4,KCNN3 and PARM1 may be potential diagnostic markers and therapeutic targets for MM.
8.Research Progress on Tyrosine Kinase Inhibitors Discontinuation in Patients with Chronic Myeloid Leukemia——Review
Jun-Xia HE ; Xi-Yuan JIANG ; Ya-Ming XI
Journal of Experimental Hematology 2025;33(1):300-305
Tyrosine kinase inhibitors(TKIs)have significantly improved the prognosis of patients with chronic myeloid leukemia(CML),and achieving treatment-free remission(TFR)has become a new goal for these patients.Various methods of discontinuing medication are continuously being explored,with successful cessation linked to factors such as the duration of TKI treatment,the sustainability of deep molecular response(DMR),transcript type,and immunological factors.Early switching of TKI,combining other therapies,and targeting leukemia stem cells may help increase the TFR rate.This article reviews the latest research developments on the exploration of TKI cessation,factors affecting TFR,selection of patients for discontinuation,strategies to enhance TFR,and monitoring after cessation,expecting to provide reference and guidance for achieving TFR in CML patients.
9.Cross-sectional survey of healthcare-associated infection in 5 736 medical institutions across China in 2024
Cui ZENG ; Wuqiang GAO ; Fu QIAO ; Hui ZHAO ; Xu FANG ; Linping LI ; Xiuwen CHEN ; Jiansen CHEN ; Dan LI ; Yuan ZHOU ; Lingli YU ; Qinglan MENG ; Xia MOU ; Lijuan XIONG ; Weiguang LI ; Ding LIU ; Jiaqing XIAO ; Limei OU ; Baozhen LI ; Jun YIN ; Haojun ZHANG ; Qiang FU ; Qun LU ; Biao WU ; Ya-wei XING ; Shumei SUN ; Shuncai WANG ; Longmin DU ; Jingping ZHANG ; Wen-ying HE ; Gui CHENG ; Nan REN ; Xun HUANG ; Anhua WU
Chinese Journal of Infection Control 2025;24(11):1572-1583
Objective To understand the current situation of healthcare-associated infection(HAI)in China,pro-vide data support and decision-making basis for formulating scientific and effective strategies for HAI prevention and control.Methods A nationwide cross-sectional survey on HAI was conducted among various types and levels of medical institutions in China according to a unified protocol of bedside surveys and case investigations.Results In 2024,a total of 5 736 medical institutions and 2 751 765 patients were surveyed.Among them,34 889 HAI cases were identified,with a prevalence rate of 1.27%.The number of HAI episodes was 38 032,and case prevalence rate was 1.38%.The prevalence rate of HAI in medical institutions in different regions of China ranged from 0.66%to 2.35%.Among medical institutions of different scales,those with a bed capacity of ≥900 had the high-est incidence of HAI,reaching 1.65%.The most common infection site was the lower respiratory tract(44.66%),followed by the urinary tract(12.94%),surgical site(9.32%),upper respiratory tract(7.02%),and bloodstream infection(5.78%).The top 3 departments with the highest HAI rates were the general intensive care unit(10.02%),department of neurosurgery(5.51%),and department(group)of hematology(5.34%).A total of 23 238 strains of HAI pathogens were detected,with 10 714 strains(46.10%)from lower respiratory tract speci-mens.The top 5 detected strains were Klebsiella pneumoniae(14.76%),Pseudomonas aeruginosa(13.33%),Escherichia coli(12.79%),Acinetobacter baumannii(9.23%),and Staphylococcus aureus(7.88%).231 944 pa-tients underwent class Ⅰ incision surgery were monitored,with 1 647 cases experienced surgical site infection,and the prevalence rate of surgical site infection was 0.71%.The number of patients who should undergo pathogen de-tection(patients receiving therapeutic and therapeutic combined prophylactic antimicrobial agents)was 715 179,while the actual number was 480 492,with a pathogen detection rate of 67.18%.425 225 patients received patho-genic detection before treatment,with a detection rate of 59.46%.Conclusion The overall HAI prevalence in Chi-na is lower,showing disparities among medical institutions of different regions and scales.Therefore,precise imple-mentation of measures is necessary for HAI prevention and control,with a focus on high-risk institutions and high-risk departments,key areas,and critical procedures.All levels of medical institutions should continuously reduce the incidence of HAI by strengthening monitoring,standardizing the use of antimicrobial agents,and reinforcing basic HAI prevention and control measures.
10.Mechanisms of Resistance to Chimeric Antigen Receptor T Cell Therapy in Hematological Malignancies and Coping Strategies
Journal of Experimental Hematology 2025;33(6):1820-1824
Chimeric antigen receptor(CAR)T cell therapy has made a major breakthrough in the treatment of hematological malignancies.However,more and more studies have shown that factors such as T-cell exhaustion,tumor antigen modulation,immunosuppressive tumor microenvironment,and CAR-T cell dysfunction can lead to relapse and CAR-T cell resistence in hematologic malignancies.Developing dual-targeted CAR-T cells,exploring new immune targets,blocking CAR-T cell exhaustion,combining CAR-T cells with other therapies,implementing bridging therapies,and designing novel immunotherapies may be strategies to address CAR-T cell resistance.This article reviews the mechanisms of resistance to CAR-T cell therapy in hematological malignancies and the corresponding coping strategies.


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