1.Perioperative immune dynamics and clinical outcomes in patients undergoing on-pump cardiac surgery
Zhiyuan CHENG ; Xinyi LIAO ; Juan WU ; Ping YANG ; Tingting WANG ; Qinjuan WU ; Wentong MENG ; Zongcheng TANG ; Jiayi SUN ; Jia TAN ; Jing LIN ; Dan LUO ; Hao WANG ; Chaonan LIU ; Jiyue XIONG ; Liqin LING ; Jing ZHOU ; Lei DU
Chinese Journal of Blood Transfusion 2026;39(1):31-43
Objective: To characterize perioperative dynamic changes in immune-cell phenotypes and inflammatory cytokines in patients undergoing CPB (cardiopulmonary bypass) cardiac surgery, and to explore their associations with postoperative outcomes. Methods: In this prospective cohort study, 120 adult patients who underwent elective cardiac surgery under CPB at West China Hospital from May 2022 to March 2023 were enrolled. Perioperative immune-cell phenotypes and concentrations of 40 inflammation-related cytokines were measured. The primary outcomes were the sequential organ failure assessment (SOFA) score at 24 h after surgery and ΔSOFA (the peak SOFA score within 48 h after surgery minus the preoperative SOFA score). Secondary outcomes included major adverse cardiovascular events (MACE), acute kidney injury (AKI), respiratory failure, severe liver injury, and infection. Results: The mean age of enrolled patients was 57±10 years. Of these, 52% (62/120) were male and 90% (108/120) underwent valve surgery. During the rewarming to the end of CPB, neutrophil counts rapidly increased (7.39×10
/L vs preoperative 3.07×10
/L, P<0.001), with significant upregulation of CD11b (7.30×10
/L vs preoperative 3.05×10
/L, P<0.001) and CD54 (7.15×10
/L vs preoperative 2.99×10
/L, P<0.001). Lymphocyte counts increased at the end of CPB (1.75×10
/L vs preoperative 1.12×10
/L, P<0.001) but decreased significantly at 24 h after surgery (0.59×10
/L vs preoperative 1.12×10
/L, P<0.001). Plasma analysis showed that multiple pro-inflammatory cytokines increased during CPB and remained elevated up to 24 h after surgery; five chemokines and the anti-inflammatory cytokine IL-10 peaked at the end of CPB. The SOFA score increased from 1 (1, 2) preoperatively to 7 (5, 10) at 24 h after surgery, with a ΔSOFA of 6 (4, 8). Within 30 days after surgery, 48 patients (40.0%) developed AKI, 17 (14.2%) developed infection, 4 (3.3%) developed severe liver injury, 3 (2.5%) developed respiratory failure, and 3 (2.5%) experienced MACE. During the 2-year follow-up, 8 patients (6.7%) experienced MACE and 5 (4.2%) died. Conclusion: Multi-organ dysfunction is common after cardiac surgery under CPB (median ΔSOFA, 6), accompanied by perioperative activation of multiple immune-cell subsets and upregulation of pro-inflammatory, anti-inflammatory, and chemotactic mediators. This study provides data-driven evidence and research clues for further investigation of the associations between CPB-related immune perturbations and postoperative organ dysfunction and clinical outcomes.
2.High-altitude exposure on retinal damage and oxidative stress levels
Quan ZHAO ; Song WANG ; Chen YIN ; Meng JING ; Juan MA ; Yan CAI
International Eye Science 2026;26(5):760-766
AIM:To investigate the effects of high-altitude hypoxic exposure on retinal injury and the associated changes in oxidative stress-related indicators in rats. METHODS: Twenty-four healthy male Sprague-Dawley(SD)rats were randomly divided into a plain group and a high-altitude group, with 12 rats(24 eyes)in each group. Rats in the plain group were housed under normoxic conditions in an SPF-grade animal facility, whereas rats in the high-altitude group were placed in a special environmental chamber simulating an altitude of 6 000 m for 7 d. Optical coherence tomography(OCT)was used to assess retinal layer architecture and quantify retinal thickness. Hematoxylin-eosin(HE)staining was performed to observe retinal histopathological changes. Immunofluorescence(IF)was used to detect the expression of hypoxia-inducible factor-1α(HIF-1α)in retinal tissue. Transmission electron microscopy(TEM)was applied to examine the ultrastructure of retinal ganglion cells(RGCs). Enzyme-linked immunosorbent assay(ELISA)was used to measure the levels of malondialdehyde(MDA), total superoxide dismutase(T-SOD), and reduced glutathione(GSH)in retinal tissue. In addition, intracellular reactive oxygen species(ROS)levels in retinal tissue were assessed using the 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA)fluorescent probe. RESULTS: OCT examination revealed disorganized retinal architecture in the high-altitude group, with increased inner and middle ring thickness and decreased outer ring thickness compared with the plain group(all P<0.05). HE staining showed varying degrees of retinal layer damage, blurred layer boundaries, loosely arranged RGCs, and partial cellular necrosis in the high-altitude group. IF analysis demonstrated significantly increased HIF-1α expression in the inner nuclear layer of the high-altitude group(P<0.01). TEM revealed mitochondrial swelling, disrupted cristae, and reduced matrix electron density in RGCs of the high-altitude group. ELISA and fluorescence probe assays showed significantly elevated MDA levels and ROS fluorescence intensity, accompanied by decreased T-SOD and GSH levels in the retinal tissue of the high-altitude group(all P<0.05). CONCLUSION: Exposure to a high-altitude hypoxic environment induces marked morphological and ultrastructural damage in the rat retina and significantly enhances oxidative stress, suggesting that oxidative stress may play a critical role in retinal injury induced by high-altitude hypoxia.
3.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.
4.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.
5.Exercise Intervention Alleviates Diabetic Sarcopenia by Regulating Lipid Metabolic Reprogramming: Mechanisms and Strategies
Meng-Lin LÜ ; Bao-Wen ZHANG ; Qian-Qian REN ; Xian-Juan KOU
Progress in Biochemistry and Biophysics 2026;53(8):2025-2040
Diabetic sarcopenia (DS) is a common but often ignored skeletal muscle complication in individuals with diabetes mellitus. It is characterized by progressive loss of skeletal muscle mass, reduced muscle strength, and impaired physical performance, which may further increase the risk of falls, disabilities, metabolic disorders, and adverse clinical outcomes. Traditionally, DS has been attributed mainly to hyperglycemia, insulin resistance, aging-related muscle decline, and chronic complications of diabetes. However, increasing evidence suggests that lipid metabolic disturbance and pathological lipid metabolic reprogramming are not merely secondary consequences of diabetes, but may actively participate in the initiation and progression of DS. Under diabetic conditions, impaired fatty acid uptake, transport, oxidation, and storage disrupt skeletal muscle metabolic homeostasis, leading to ectopic lipid deposition and accumulation of lipotoxic intermediates. These lipid-derived metabolites can aggravate insulin resistance, impair mitochondrial energy production, enhance oxidative stress, activate chronic low-grade inflammation, and disturb protein synthesis and degradation balance, thereby accelerating skeletal muscle atrophy and functional decline. Lipid metabolic dysregulation may also interact with multiple pathological processes involved in DS, including mitochondrial dysfunction, inflammatory signaling, oxidative damage, impaired autophagy, and gut microbiota imbalance. These mechanisms do not occur independently; instead, they form a complex bidirectional vicious cycle with diabetes-related metabolic disorders. Specifically, mitochondrial dysfunction reduces fatty acid oxidative capacity, which further promotes lipid accumulation and lipotoxicity. Inflammatory activation can impair insulin signaling and muscle protein metabolism, while lipid overload may in turn amplify inflammatory responses. Similarly, gut microbiota dysbiosis and altered microbial metabolites may influence systemic inflammation, lipid metabolism, and skeletal muscle homeostasis. Therefore, lipid metabolic reprogramming provides an important mechanistic perspective for understanding the progression of DS from metabolic disturbance to structural and functional muscle impairment. Exercise intervention is an effective and clinically feasible non-pharmacological strategy for the prevention and management of DS. Both aerobic exercise and resistance training have been shown to improve insulin sensitivity, enhance fatty acid oxidation, increase mitochondrial biogenesis, reduce ectopic lipid deposition, and attenuate lipotoxic metabolite accumulation. These adaptations not only improved glucose and lipid metabolism, but also increased the preservation of muscle mass, muscle strength, and physical function. Moreover, combined exercise strategies may provide complementary benefits by integrating the metabolic advantages of aerobic exercise with the anabolic and functional effects of resistance training. Based on analyses of publicly available datasets and literature evidences, this review systematically summarizes the role of lipid metabolic disorders in the pathogenesis of DS, with particular attention to the molecular mechanisms linking lipid dysregulation to insulin resistance, chronic inflammation, oxidative stress, mitochondrial dysfunction, and gut microbiota disturbance. Furthermore, this review discusses the potential mechanisms by which exercise intervention improves DS through the regulation of lipid metabolic reprogramming, and outlines exercise prescription strategies in terms of modality, intensity, frequency, and duration. Understanding the interaction between lipid metabolism and skeletal muscle dysfunction may provide new theoretical evidence for early identification, mechanistic research, and precision exercise therapy in DS. Overall, targeting pathological lipid metabolic reprogramming through exercise intervention represents a promising and clinically actionable approach for improving muscle health and prognosis in individuals with DS.
6.Study on accumulation of polysaccharide and steroid components in Polyporus umbellatus infected by Armillaria spp.
Ming-shu YANG ; Yi-fei YIN ; Juan CHEN ; Bing LI ; Meng-yan HOU ; Chun-yan LENG ; Yong-mei XING ; Shun-xing GUO
Acta Pharmaceutica Sinica 2025;60(1):232-238
In view of the few studies on the influence of
7.Neutrophil activation is correlated with acute kidney injury after cardiac surgery under cardiopulmonary bypass
Tingting WANG ; Yuanyuan YAO ; Jiayi SUN ; Juan WU ; Xinyi LIAO ; Wentong MENG ; Min YAN ; Lei DU ; Jiyue XIONG
Chinese Journal of Blood Transfusion 2025;38(3):358-367
[Objective] To explore the relationship between neutrophil activation under cardiopulmonary bypass (CPB) and the incidence of cardiac surgery-associated acute kidney injury (CS-AKI). [Methods] This prospective cohort study enrolled adult patients who scheduled for cardiac surgery under CPB at West China Hospital between May 1, 2022 and March 31, 2023. The primary outcome was acute kidney injury (AKI). Blood samples (5 mL) were obtained from the central vein before surgery, at rewarming, at the end of CPB, and 24 hours after surgery. Neutrophils were labeled with CD11b, CD54 and other markers. To assess the effect of neutrophils activation on AKI, propensity score matching (PSM) was employed to equilibrate covariates between the groups. [Results] A total of 120 patients included into the study, and 17 (14.2%) developed AKI. Both CD11b+ and CD54+ neutrophils significantly increased during the rewarming phase and the increases were kept until 24 hours after surgery. During rewarming, the numbers of CD11b+ neutrophils were significantly higher in AKI compared to non-AKI (4.71×109/L vs 3.31×109/L, Z=-2.14, P<0.05). Similarly, the CD54+ neutrophils counts were also significantly higher in AKI than in non-AKI before surgery (2.75×109/L vs 1.79×109/L, Z=-2.99, P<0.05), during rewarming (3.12×109/L vs 1.62×109/L, Z=-4.34, P<0.05), and at the end of CPB (4.28×109/L vs 2.14×109/L, Z=-3.91, P<0.05). An analysis of 32 matched patients (16 in each group) revealed that CD11b+ and CD54+ neutrophil levels of AKI were 1.74 folds (4.83×109/L vs 2.77×109/L, Z=-2.72, P<0.05) and 2.34 folds (3.32×109/L vs 1.42×109/L, Z=-4.12, P<0.05), respectively, of non-AKI at rewarming phase. [Conclusion] Neutrophils are activated during CPB, and they can be identified by CD11b/CD54 markers. The activated neutrophils of AKI patients are approximately 2 folds of non-AKI during the rewarming phase, with disparity reached peak between groups during rewarming. These findings suggest the removal of 50% of activated neutrophils during the rewarming phase may be effective to reduce the risk of AKI.
8.Targeted Therapy for Rheumatoid Arthritis in the New Era
Medical Journal of Peking Union Medical College Hospital 2025;16(1):19-27
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. The clinical manifestation of RA involves various organs and systems both inside and outside the joints, and often exhibits strong clinical heterogeneity with unclear pathogenesis. Ineffective drug treatment for severe arthritis can result in physical disability and severely decreased quality of life. In recent years, targeted therapy for RA has become a hot research topic and has made new breakthroughs. Targeted treatments for RA mainly include two categories: biologic and targeted synthetic disease-modifying antirheumatic drugs. This article aims to elaborate on the current research status and progress of these drugs, with the hope of providing insights for clinicians to better guide personalized treatment for RA patients.
9.Trends in incidence and mortality of lung cancer in Huangpu District from 2002 to 2019
QIU Fengqian ; ZHAO Junfeng ; CHEN Weihua ; DU Juan ; JI Yunfang ; GAO Shuna ; MENG Jie ; HE Lihua ; CHEN Bo ; ZHANG Yan
Journal of Preventive Medicine 2025;37(2):143-147
Objective:
To investigate the trends in incidence and mortality of lung cancer in Huangpu District, Shanghai Municipality from 2002 to 2019, so as to provide the evidence for formulating lung cancer prevention and control measures.
Methods:
Data of lung cancer incidence and mortality among residents in Huangpu District from 2002 to 2019 were collected through the Shanghai Cancer Registration and Reporting Management System. The crude incidence and mortality of lung cancer was calculated, and standardized by the data from the Chinese Fifth National Population Census in 2000 (Chinese-standardized rate) and the Segi's world standard population in 1960 (world-standardized rate). The trends in incidence and mortality of lung cancer among residents by age and gender were evaluated using annual percent change (APC).
Results:
A total of 12 965 cases of lung cancer were reported in Huangpu District from 2002 to 2019, and the crude incidence rate was 80.66/105, the Chinese-standardized incidence rate was 34.54/105, and the world-standardized incidence rate was 31.30/105, all showing upward trends (APC=4.588%, 2.933% and 3.247%, all P<0.05). A total of 10 102 deaths of lung cancer were reported, and the crude mortality rate was 62.30/105, showing an upward trend (APC=0.959%, P<0.05); the Chinese-standardized mortality was 25.93/105, and the world-standardized mortality was 22.05/105, both showing downward trends (APC=-1.282% and -1.263%, both P<0.05). The crude incidence and mortality rates of lung cancer in males were higher than those in females (101.39/105 vs. 60.52/105, 85.45/105 vs. 39.87/105, both P<0.05). The crude incidence and mortality rates of lung cancer showed upward trends with age (both P<0.05), reaching their peaks in the age groups of 80-<85 years (341.37/105) and 85 years or above (355.97/105), respectively.
Conclusions
The incidence of lung cancer showed an upward trend, while the mortality showed a downward trend in Huangpu District from 2002 to 2019. Elderly men were the high-risk group for lung cancer incidence and mortality.
10.Loss-of-function MAVS mutation causes antiviral immunodeficiency:unveiling a novel mechanism linking viral infection to generalized pustular psoriasis in children
Yanan SUN ; Jiahong ZHOU ; Yaqin LIU ; Juan YANG ; Shasha MENG ; Hongmei LI ; Weihui ZHOU
Journal of Army Medical University 2025;47(23):2953-2962
Objective To investigate the role of mitochondrial antiviral signaling protein(MAVS)in viral infection-triggered generalized pustular psoriasis(GPP)in children.Methods This retrospective case-control study enrolled 80 GPP patients aged 0~18 years from Children's Hospital of Chongqing Medical University(from October 2013 to April 2019).Whole-exome sequencing identified rare MAVS variants associated with GPP.Pathogenicity of variants was predicted using Mutation Taster,Disease Association,SIFT,and CADD bioinformatics tools.Sanger sequencing validated variants,followed by construction of wild-type(WT)and mutant MAVS expression plasmids transfected into HEK 293 cells.Protein expression was assessed by Western blot.Dual-luciferase reporter gene assays measured IFNB1 and NF-κB transcriptional activity.Genotype distribution of the MAVS c.171dupT/p.H57fs variant was analyzed using Fisher's exact test.Results This study enrolled 80 pediatric GPP patients(aged 0~18 years).Whole-exome sequencing identified five rare MAVS variants,with bioinformatics analyses predicting deleterious effects on protein stability and function.Western blot demonstrated that the c.171dupT mutation in GPP patients significantly reduced full-length MAVS expression(P<0.001);dual-luciferase assays further revealed this variant impaired MAVS-mediated IFNB1 transcriptional activation by 85%(P<0.001),abrogated NF-κB signaling pathway activation(P<0.001),but exhibited no dominant-negative effect on wild-type MAVS function(P>0.05).Conclusion The MAVS c.171dupT frameshift variant may contribute to infection-triggered GPP in children,suggesting its potential as a genetic biomarker for GPP susceptibility.


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