1.Schwann cells promote peripheral nerve regeneration:retrospect and prospect
Zhenyi FU ; Junhao LI ; Yating ZHANG ; Yunkai HE ; Junyu LIU ; Yunhao WEI ; Jiaxin LIU
Chinese Journal of Tissue Engineering Research 2026;30(5):1236-1246
BACKGROUND:Peripheral nerve axon rupture seriously affects patients' physical function and mental health.Microsurgery,nerve autograft,nerve allograft,fibrin glue and catheter technology are the main treatments for peripheral nerve injury,each of which has its own advantages and disadvantages,but the overall treatment effect is not satisfactory.Despite the clinical success of Schwann cells in promoting axonal regeneration,there are still many challenges in the treatment with Schwann cells,such as slow expansion of Schwann cells,immune rejection,and low survival rate of transplanted cells.OBJECTIVE:To summarize the role and mechanism of Schwann cells in promoting the regeneration of peripheral nerve axons,and the difficulties and challenges of Schwann cells in the process of nerve regeneration treatment.METHODS:PubMed,Medline,WanFang,VIP,and CNKI were searched by computer using the search terms of"Schwann cells,synaptic Schwann cell,macrophage,peripheral nerve axon rupture,Wallerian degeneration,Peripheral nerve axon regeneration,Central nervous system repair"in English and Chinese.Literature related to Schwann cell proliferation and differentiation,promotion of peripheral nerve regeneration,and clinical applications was retrieved from database inception to October 2024,and a total of 95 articles were finally included for review.RESULTS AND CONCLUSION:Schwann cells interact with macrophages,T cells and other cells,to initiate the regeneration process through signaling pathways,including Krox20/C-Jun,NRG-1/ErbB,Notch,MAPK,and PI3K/Akt/mTOR,synthesize and release nerve growth factors,and thus promote regeneration of the peripheral nervous system.Schwann cells have been experimentally demonstrated to have great potential in peripheral nerve repair and are expected to become the key target of therapeutic intervention.However,there are still problems such as difficulties in cell harvest and culture,as well as the occurrence of other diseases during the treatment process.
2.Schwann cells promote peripheral nerve regeneration:retrospect and prospect
Zhenyi FU ; Junhao LI ; Yating ZHANG ; Yunkai HE ; Junyu LIU ; Yunhao WEI ; Jiaxin LIU
Chinese Journal of Tissue Engineering Research 2026;30(5):1236-1246
BACKGROUND:Peripheral nerve axon rupture seriously affects patients' physical function and mental health.Microsurgery,nerve autograft,nerve allograft,fibrin glue and catheter technology are the main treatments for peripheral nerve injury,each of which has its own advantages and disadvantages,but the overall treatment effect is not satisfactory.Despite the clinical success of Schwann cells in promoting axonal regeneration,there are still many challenges in the treatment with Schwann cells,such as slow expansion of Schwann cells,immune rejection,and low survival rate of transplanted cells.OBJECTIVE:To summarize the role and mechanism of Schwann cells in promoting the regeneration of peripheral nerve axons,and the difficulties and challenges of Schwann cells in the process of nerve regeneration treatment.METHODS:PubMed,Medline,WanFang,VIP,and CNKI were searched by computer using the search terms of"Schwann cells,synaptic Schwann cell,macrophage,peripheral nerve axon rupture,Wallerian degeneration,Peripheral nerve axon regeneration,Central nervous system repair"in English and Chinese.Literature related to Schwann cell proliferation and differentiation,promotion of peripheral nerve regeneration,and clinical applications was retrieved from database inception to October 2024,and a total of 95 articles were finally included for review.RESULTS AND CONCLUSION:Schwann cells interact with macrophages,T cells and other cells,to initiate the regeneration process through signaling pathways,including Krox20/C-Jun,NRG-1/ErbB,Notch,MAPK,and PI3K/Akt/mTOR,synthesize and release nerve growth factors,and thus promote regeneration of the peripheral nervous system.Schwann cells have been experimentally demonstrated to have great potential in peripheral nerve repair and are expected to become the key target of therapeutic intervention.However,there are still problems such as difficulties in cell harvest and culture,as well as the occurrence of other diseases during the treatment process.
3.Effect of Modified Xiangsha Liujunzitang on Hepatic Kupffer Cell Inflammation Mediated by Intestinal-derived LPS in Rats with Hyperlipidemia and Spleen Deficiency Syndrome
Mengzhu CHE ; Lianqun JIA ; Dongyu MIN ; Guoyuan SUI ; Qi ZHANG ; Guanlin YANG ; Yunhao CUI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(16):77-86
ObjectiveThe study aims to investigate the intervention effect of modified Xiangsha Liujunzitang (M-XSLJZ) on intestinal-derived lipopolysaccharide (LPS)-activated Kupffer cell inflammation in rats with hyperlipidemia spleen deficiency syndrome. MethodsSeventy male SD rats were randomly divided into seven groups (n=10): blank control (CON), high-fat diet without spleen deficiency (HFD), high-fat diet with spleen deficiency (SD-HFD), M-XSLJZ low-, medium-, and high-dose groups (XS-L, XS-M, XS-H), and western medicine control (R). Spleen deficiency was induced in SD-HFD, XS-L, XS-M, XS-H, and R groups via irregular diet combined with exhaustive swimming for 15 days. The CON group received a standard diet, while other groups were fed a high-fat diet for 10 weeks to establish the hyperlipidemia model. After successful modeling, rats were treated for 8 weeks: M-XSLJZ was administered at 3.51, 7.02, 14.04 g·kg-1 in XS-L, XS-M, and XS-H groups, respectively. The R group received 9×10-4 g·kg-1 of a reference drug. D-xylose excretion rate was measured by the phloroglucinol method. Blood lipids were assessed using an automated biochemical analyzer. Hematoxylin-eosin (HE) staining was used to evaluate the pathological conditions of the liver, and oil red O staining was used to observe the lipid deposition in the liver. The levels of LPS, portal vein serum LPS, LPS-binding protein (LBP), serum interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA). Immunofluorescence was used to evaluate CD86 expression and CD68/TLR4 co-localization in the liver. Protein levels of TLR4, MyD88, NF-κB p65, and p-NF-κB p65 in Kupffer cells were analyzed via Western blot automated protein analysis. Hepatic IL-6, TNF-α, and IL-1β mRNA and protein levels were measured using Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) and Western blot. ResultsCompared with the CON group, the SD-HFD group showed a decrease in D-xylose excretion (P<0.01). TC, TG, HDL-C, and LDL-C increased (P<0.05, P<0.01). A large number of hepatic lipid vacuoles and orange-red lipid droplet deposition appeared in the liver. Ileal LPS, portal LPS, and LBP increased (P<0.05, P<0.01). The levels of serum IL-6, TNF-α, and IL-1β increased (P<0.01). The expression of CD86 was upregulated (P<0.01), and the co-expression of CD68 and TLR4 was enhanced. The protein levels of TLR4, MyD88, and p-p65 in Kupffer cells increased (P<0.01). The mRNA and protein levels of IL-6, TNF-α, and IL-1β increased (P<0.05, P<0.01). Compared with the HFD group, the SD-HFD group exhibited decreased D-xylose excretion (P<0.01), higher HDL-C, LDL-C (P<0.05), increased portal LBP and LPS (P<0.05), increased serum IL-6 and TNF-α (P<0.01), upregulated CD86 (P<0.01), enhanced CD68/TLR4 co-expression, and higher TNF-α mRNA/protein (P<0.05). Compared with the SD-HFD group, all M-XSLJZ treatment groups showed reduced TC, TG, and LDL-C (P<0.05, P<0.01). XS-H and R groups displayed improved hepatic lipid deposition. XS-H and R groups had lower ileal LPS, portal LPS, and LBP levels (P<0.05, P<0.01). All M-XSLJZ treatment groups exhibited reduced serum IL-6, IL-1β, and TNF-α (P<0.01). The XS-H group showed downregulated CD86 (P<0.01) and weakened CD68/TLR4 co-expression. The XS-H group had reduced TLR4, MyD88, and p-NF-κB p65 in Kupffer cells (P<0.01). XS-H and R groups showed lower IL-6, TNF-α, and IL-1β mRNA/protein (P<0.05, P<0.01). ConclusionM-XSLJZ may exert its lipid-lowering effects by inhibiting intestinal-derived LPS and alleviating Kupffer cell inflammation in the liver.
4.Peptide-based immuno-PET/CT monitoring of dynamic PD-L1 expression during glioblastoma radiotherapy
Yong WANG ; Kewen HE ; Yang ZHANG ; Yunhao CHEN ; Shijie WANG ; Kunlong ZHAO ; Zhiguo LIU ; Man HU
Journal of Pharmaceutical Analysis 2025;15(3):599-609
Real-time,noninvasive programmed death-ligand 1(PD-L1)testing using molecular imaging has enhanced our understanding of the immune environments of neoplasms and has served as a guide for immunotherapy.However,the utilization of radiotracers in the imaging of human brain tumors using positron emission tomography/computed tomography(PET/CT)remains limited.This investigation involved the synthesis of[18F]AlF-NOTA-PCP2,which is a novel peptide-based radiolabeled tracer that targets PD-L1,and evaluated its imaging capabilities in orthotopic glioblastoma(GBM)models.Using this tracer,we could noninvasively monitor radiation-induced PD-L1 changes in GBM.[18F]AlF-NOTA-PCP2 exhibited high radiochemical purity(>95%)and stability up to 4 h after synthesis.It demonstrated specific,high-affinity binding to PD-L1 in vitro and in vivo,with a dissociation constant of 0.24 nM.PET/CT imaging,integrated with contrast-enhanced magnetic resonance imaging,revealed significant accumulation of[18F]AlF-NOTA-PCP2 in orthotopic tumors,correlating with blood-brain barrier disruption.After radiotherapy(15 Gy),[18F]AlF-NOTA-PCP2 uptake in tumors increased from 9.51%±0.73%to 12.04%±1.43%,indicating enhanced PD-L1 expression consistent with immunohisto-chemistry findings.Fractionated radiation(5 Gy × 3)further amplified PD-L1 upregulation(13.9%±1.54%ID/cc)compared with a single dose(11.48%±1.05%ID/cc).Taken together,[18F]AlF-NOTA-PCP2 may be a valuable tool for noninvasively monitoring PD-L1 expression in brain tumors after radiotherapy.
5.Development of wireless IoT acquisition terminal for medical equipment based on Wi-Fi 6
Nan ZHANG ; Jing LI ; Weijiao ZHANG ; Bin ZHANG ; Yunhao ZHOU ; Kunlun HE ; Desen CAO
China Medical Equipment 2025;22(2):1-8
Objective:In order to meet the needs of building Internet of Things(IoT)of medical equipment for mobile deployment,rapid deployment,high-speed and stable data transmission,a wireless IoT acquisition terminal for medical equipment on the basis of Wi-Fi 6 was developed.Methods:Wi-Fi 6 technique was adopted to construct IoT of medical equipment,and the data acquisition terminal included Wi-Fi 6-based customer premises equipment(CPE)and intelligent wireless access point(AP).The CPE adopted a domestic main control chip and Wi-Fi chips,which included two 2.4G and 5G antennas,and was compatible with multiple interfaces such as RS232 and RJ45.The data of medical equipment were converted into wireless transmission through wired communication interfaces.The security access and data traceability of medical equipment were supported through secure secondary authentication with security control enhanced by"white list plus certificate".The intelligent wireless AP was compatible with various RF devices such as Wi-Fi,bluetooth,radio frequency identification,etc.(included 2.4G and 5G antennas).CPE and AP jointly apply dual-transmitter selection technique to ensure stable data transmission.Results:The key performance of wireless IoT acquisition terminals has been tested,and the results indicated that the integrity of acquisition data of intelligent acquisition terminal was consistent with that of output data,with a maximum latency of 9 ms and an average latency of 2 ms.The tested results can meet the expected requirements.Conclusion:The wireless IoT data of medical equipment that based on the acquisition terminal can stably and quickly collect data of equipment to IoT platform,providing paradigm for the construction of wireless IoT of medical equipment.
6.Peptide-based immuno-PET/CT monitoring of dynamic PD-L1 expression during glioblastoma radiotherapy.
Yong WANG ; Kewen HE ; Yang ZHANG ; Yunhao CHEN ; Shijie WANG ; Kunlong ZHAO ; Zhiguo LIU ; Man HU
Journal of Pharmaceutical Analysis 2025;15(3):101082-101082
Real-time, noninvasive programmed death-ligand 1 (PD-L1) testing using molecular imaging has enhanced our understanding of the immune environments of neoplasms and has served as a guide for immunotherapy. However, the utilization of radiotracers in the imaging of human brain tumors using positron emission tomography/computed tomography (PET/CT) remains limited. This investigation involved the synthesis of [18F]AlF-NOTA-PCP2, which is a novel peptide-based radiolabeled tracer that targets PD-L1, and evaluated its imaging capabilities in orthotopic glioblastoma (GBM) models. Using this tracer, we could noninvasively monitor radiation-induced PD-L1 changes in GBM. [18F]AlF-NOTA-PCP2 exhibited high radiochemical purity (>95%) and stability up to 4 h after synthesis. It demonstrated specific, high-affinity binding to PD-L1 in vitro and in vivo, with a dissociation constant of 0.24 nM. PET/CT imaging, integrated with contrast-enhanced magnetic resonance imaging, revealed significant accumulation of [18F]AlF-NOTA-PCP2 in orthotopic tumors, correlating with blood-brain barrier disruption. After radiotherapy (15 Gy), [18F]AlF-NOTA-PCP2 uptake in tumors increased from 9.51% ± 0.73% to 12.04% ± 1.43%, indicating enhanced PD-L1 expression consistent with immunohistochemistry findings. Fractionated radiation (5 Gy × 3) further amplified PD-L1 upregulation (13.9% ± 1.54% ID/cc) compared with a single dose (11.48% ± 1.05% ID/cc). Taken together, [18F]AlF-NOTA-PCP2 may be a valuable tool for noninvasively monitoring PD-L1 expression in brain tumors after radiotherapy.
7.Development of wireless IoT acquisition terminal for medical equipment based on Wi-Fi 6
Nan ZHANG ; Jing LI ; Weijiao ZHANG ; Bin ZHANG ; Yunhao ZHOU ; Kunlun HE ; Desen CAO
China Medical Equipment 2025;22(2):1-8
Objective:In order to meet the needs of building Internet of Things(IoT)of medical equipment for mobile deployment,rapid deployment,high-speed and stable data transmission,a wireless IoT acquisition terminal for medical equipment on the basis of Wi-Fi 6 was developed.Methods:Wi-Fi 6 technique was adopted to construct IoT of medical equipment,and the data acquisition terminal included Wi-Fi 6-based customer premises equipment(CPE)and intelligent wireless access point(AP).The CPE adopted a domestic main control chip and Wi-Fi chips,which included two 2.4G and 5G antennas,and was compatible with multiple interfaces such as RS232 and RJ45.The data of medical equipment were converted into wireless transmission through wired communication interfaces.The security access and data traceability of medical equipment were supported through secure secondary authentication with security control enhanced by"white list plus certificate".The intelligent wireless AP was compatible with various RF devices such as Wi-Fi,bluetooth,radio frequency identification,etc.(included 2.4G and 5G antennas).CPE and AP jointly apply dual-transmitter selection technique to ensure stable data transmission.Results:The key performance of wireless IoT acquisition terminals has been tested,and the results indicated that the integrity of acquisition data of intelligent acquisition terminal was consistent with that of output data,with a maximum latency of 9 ms and an average latency of 2 ms.The tested results can meet the expected requirements.Conclusion:The wireless IoT data of medical equipment that based on the acquisition terminal can stably and quickly collect data of equipment to IoT platform,providing paradigm for the construction of wireless IoT of medical equipment.
8.Visualization of Brain Abnormal β-Amyloid Deposition in Alzheimer's Disease Based on 18F-Florbetaben PET Imaging
Huamei LIN ; Yunhao YANG ; Jiaying LU ; Zhengwei ZHANG ; Shufen CHEN ; Jingjie GE ; Yihui GUAN ; Chuantao ZUO
Chinese Journal of Medical Imaging 2024;32(5):420-425
Purpose To investigate the characteristics of 18F-Florbetaben(18F-FBB)β-amyloid(Aβ)PET imaging in different brain regions of Alzheimer's disease(AD)patients with different degrees of cognitive impairment,and to explore the correlation between Aβ deposition and cognitive dysfunction.Materials and Methods A total of eighteen patients with a clinical diagnosis of probable AD from August 2022 to October 2023 were retrospectively included in Huashan Hospital.All patients had Aβ abnormal deposition in the brain as confirmed by 18F-FBB PET imaging.According to the severity of symptoms,they were divided into the AD-induced mild cognitive impairment(MCI)group(8 cases)and the dementia group(10 cases).In addition,12 healthy controls were included.First,the standardized uptake value ratio of abnormal Aβ deposition in the frontal lobe,lateral parietal lobe,lateral temporal lobe,anterior and posterior cingulate gyrus,and compound cortex was semi-quantitatively calculated and compared among the three groups based on the subjects'brain MRI and automated anatomical labeling template.The correlation between the degree of Aβ deposition in the brains of AD patients and cognitive scale scores(mini-mental state examination,Montreal cognitive assessment)was then further analyzed.Results The standardized uptake value ratio values of Aβabnormal deposition in the frontal lobe,lateral temporal lobe,lateral parietal lobe,anterior and posterior cingulate cortex and compound cortex in the AD-induced MCI and dementia groups were significantly higher than those in the healthy controls(t=7.442-9.151,all P<0.05).However,there was no significant difference in the standardized uptake value ratio values of Aβ abnormal deposition in the above brain regions between the MCI and dementia groups(t=0.312-0.996,all P>0.05).In addition,there was no significant correlation between the degree of Aβ deposition in the brain and the cognitive scale scores(mini-mental state examination,Montreal cognitive assessment)in the AD-induced MCI and dementia groups(r=-0.049-0.050,all P>0.05).Conclusion Aβ deposition in the brains of AD-induced MCI and dementia is significantly higher than in the healthy controls.However,Aβ deposition cannot identify AD patients with different degrees of cognitive impairment,reflecting that Aβ deposition has certain limitations in assessing the severity of clinical symptoms of AD.
9.Effects of long-term exposure to ambient fine particulate matter on diabetes mellitus and the moderating effects of diet
Jinxia WANG ; Yunhao SHI ; Dongshuai WANG ; Xuehao DONG ; Hanqing ZHANG ; Sijie ZHOU ; Yi ZHAO ; Yuhong ZHANG ; Yajuan ZHANG
Journal of Environmental and Occupational Medicine 2024;41(3):259-266
Background Long-term exposure to ambient fine particulate matter (PM2.5) may increase the risk of diabetes, and a healthy diet can effectively control fasting blood glucose levels. However, it is unclear whether dietary factors have a moderating effect on the risk of diabetes associated with atmospheric PM2.5 exposure. Objective To investigate the association between long-term exposure to PM2.5 and diabetes in rural areas of Ningxia, and potential interaction of long-term exposure to atmospheric PM2.5 and diet on diabetes. Methods The study subjects were selected from the baseline survey data of the China Northwest Cohort-Ningxia (CNC-NX) , a natural population cohort. A total of 13917 subjects were included, excluding participants with missing covariate information. We utilized the annual average ambient PM2.5 concentration from 2014 to 2018 as the long-term exposure level. Logistic regression and multiple linear regression were employed to analyze the associations of long-term atmospheric PM2.5 exposure with diabetes and fasting blood glucose levels. Stratification by frequency of vegetable consumption, frequency of fruit consumption, and salty taste was used to examine moderating effects on the diabetes risk associated with atmospheric PM2.5 exposure. Results The mean age of the 13917 subjects was (56.8±10.0) years, and the prevalence of diabetes was 9.8%. Between 2014 and 2018, the average annual concentration of PM2.5 was (38.10±4.67) μg·m−3. The risk (OR) of diabetes was 1.018 (95%CI: 1.005, 1.032) and the fasting blood glucose was increased by 0.011 (95%CI: 0.004, 0.017) mmol·L−1 for each 1 μg·m−3 increase in PM2.5 concentration. Compared to those who consumed vegetables < 1 time per week, individuals who consume vegetables 1-3 times per week and ≥4 times per week had a reduced risk of developing diabetes by 27.1% (OR=0.729, 95%CI: 0.594, 0.893) and 16.8% (OR=0.832, 95%CI: 0.715, 0.971) respectively. Similarly, when compared to those who consumed fruits <1 time per week, individuals who consumed fruits 1-3 times per week and ≥4 times per week exhibited a reduced risk of diabetes by 16.4% (OR=0.836, 95%CI: 0.702, 0.998) and 18.2% (OR=0.818, 95%CI: 0.700, 0.959) respectively. Fasting blood glucose decreased by 0.202 (95%CI: -0.304, -0.101) mmol·L−1 in participants who ate vegetables 1-3 times per week. The effect of salty taste on diabetes and fasting blood glucose was not significant. The results of stratified analysis by dietary factors and PM2.5 concentration showed that the risks of diabetes were increased in the low PM2.5 pollution-low vegetable intake frequency group and the high PM2.5 pollution-low vegetable intake frequency group compared with the low PM2.5 pollution-high vegetable intake frequency group, with OR values of 3.987 (95%CI: 2.943, 5.371) and 1.433 (95%CI: 1.143, 1.796) respectively. The risk of diabetes was 50.1% higher in participants with high PM2.5 pollution and low fruit intake frequency than in participants with low PM2.5 pollution and high fruit intake frequency (OR=1.501, 95%CI: 1.171, 1.926). No interaction was found between salty taste and PM2.5 on diabetes. Conclusion Long-term exposure to ambient PM2.5 is associated with an increased fasting blood glucose and an elevated risk of diabetes in rural Ningxia population. Increasing the frequency of weekly consumption of vegetables or fruits may have a certain protective effect against diabetes occurrence, as well as a moderating effect on diabetes and fasting blood glucose levels associated with long-term exposure to atmospheric PM2.5.
10.Artificial intelligence system for outcome evaluations of human in vitro fertilization-derived embryos
Ling SUN ; Jiahui LI ; Simiao ZENG ; Qiangxiang LUO ; Hanpei MIAO ; Yunhao LIANG ; Linling CHENG ; Zhuo SUN ; Hou Wa TAI ; Yibing HAN ; Yun YIN ; Keliang WU ; Kang ZHANG
Chinese Medical Journal 2024;137(16):1939-1949
Background::In vitro fertilization (IVF) has emerged as a transformative solution for infertility. However, achieving favorable live-birth outcomes remains challenging. Current clinical IVF practices in IVF involve the collection of heterogeneous embryo data through diverse methods, including static images and temporal videos. However, traditional embryo selection methods, primarily reliant on visual inspection of morphology, exhibit variability and are contingent on the experience of practitioners. Therefore, an automated system that can evaluate heterogeneous embryo data to predict the final outcomes of live births is highly desirable. Methods::We employed artificial intelligence (AI) for embryo morphological grading, blastocyst embryo selection, aneuploidy prediction, and final live-birth outcome prediction. We developed and validated the AI models using multitask learning for embryo morphological assessment, including pronucleus type on day 1 and the number of blastomeres, asymmetry, and fragmentation of blastomeres on day 3, using 19,201 embryo photographs from 8271 patients. A neural network was trained on embryo and clinical metadata to identify good-quality embryos for implantation on day 3 or day 5, and predict live-birth outcomes. Additionally, a 3D convolutional neural network was trained on 418 time-lapse videos of preimplantation genetic testing (PGT)-based ploidy outcomes for the prediction of aneuploidy and consequent live-birth outcomes.Results::These two approaches enabled us to automatically assess the implantation potential. By combining embryo and maternal metrics in an ensemble AI model, we evaluated live-birth outcomes in a prospective cohort that achieved higher accuracy than experienced embryologists (46.1% vs. 30.7% on day 3, 55.0% vs. 40.7% on day 5). Our results demonstrate the potential for AI-based selection of embryos based on characteristics beyond the observational abilities of human clinicians (area under the curve: 0.769, 95% confidence interval: 0.709–0.820). These findings could potentially provide a noninvasive, high-throughput, and low-cost screening tool to facilitate embryo selection and achieve better outcomes. Conclusions::Our study underscores the AI model’s ability to provide interpretable evidence for clinicians in assisted reproduction, highlighting its potential as a noninvasive, efficient, and cost-effective tool for improved embryo selection and enhanced IVF outcomes. The convergence of cutting-edge technology and reproductive medicine has opened new avenues for addressing infertility challenges and optimizing IVF success rates.

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