1.Antibacterial effects of platelets on five common pathogenic bacteria: a comparative analysis
Erxiong LIU ; Wenting WANG ; Jinmei XU ; Ning AN ; Yafen WANG ; Jieyun SHI ; Lingling ZHANG ; Yaozhen CHEN ; Wen YIN
Chinese Journal of Blood Transfusion 2025;38(6):747-758
Objective: To compare and analyze the antibacterial effects of platelets against five common clinical pathogenic bacteria including MRSA, SE, SA, E. coli, and CRKP, and to preliminarily explore the role of DCD sensitivity in the observed variations of antibacterial effects. Methods: The same number of platelets were used to establish co-culture systems of platelets and platelet lysates with the five pathogenic bacteria. The antibacterial effects of platelets and platelet lysates on the five pathogenic bacteria were evaluated by observing the turbidity of the bacterial solution, measuring the OD
value of the bacterial solution and counting the colonies. The supernatant protein of platelets co-cultured with MRSA was collected for quantitative proteomics analysis to explore the important antibacterial proteins of platelets. The content of DCD in the supernatant after co-culture of platelets and platelet lysates with the five pathogenic bacteria was detected by ELISA to preliminarily analyze the reasons for the different antibacterial effects of platelets on the five pathogenic bacteria. Results: Compared with the control group of MRSA, SA, and SE, the turbidity of the bacterial solution decreased after co-culture of platelets and platelet lysates with MRSA, SA, and SE for 12 h, and the OD
value and colony count were significantly reduced (P<0.05). The turbidity of the bacterial solution did not change significantly after co-culture of platelets and platelet lysates with E. coli for 24 h, but the OD
value decreased (P<0.05), and the colony count decreased to 10
CFU/mL but the difference was not statistically significant (P>0.05). Compared with the control group of CRKP, the turbidity, OD
value, and colony count of the bacterial solution did not change significantly after co-culture of platelets and platelet lysates with CRKP (P>0.05). Proteomics results showed that after co-culture with MRSA, important proteins related to platelet activation, including collagen, fibrinogen, von Willebrand factor, integrin αIIbβ3, platelet glycoprotein V and IV were significantly up-regulated. ELISA results showed that after co-culture with the five pathogenic bacteria, platelets could secrete a large amount of DCD, with the content around 3 μg/mL. Conclusion: The antibacterial effect of platelets on Gram-positive bacteria MRSA, SA, and SE is better than that on Gram-negative bacteria E. coli and CRKP, and platelets have the best antibacterial effect on MRSA. The differences in antibacterial effects of platelets on the five pathogenic bacteria may be related to the sensitivity of DCD antibacterial peptides to the five pathogenic bacteria.
2.Investigation and analysis of adult skeletal fluorosis caused by drinking tea-type endemic fluorosis in Yushu Tibetan Autonomous Prefecture, Qinghai Province in 2021
Guanglan PU ; Mingjun WANG ; Yanan LI ; Xin ZHOU ; Peizhen YANG ; Ping CHEN ; Qing LU ; Xun CHEN ; Hongting SHEN ; Jing MA ; Jinmei ZHANG ; Cuiling LA ; Qiang ZHANG ; Xianya MENG
Chinese Journal of Endemiology 2024;43(3):207-211
Objective:To investigate the prevalence of adult skeletal fluorosis caused by drinking tea-type endemic fluorosis in Yushu Tibetan Autonomous Prefecture (hereinafter referred to as Yushu Prefecture), Qinghai Province, and provide scientific basis for prevention and control of the disease.Methods:In August 2021, one village was selected as a survey site in six counties (cities) in Yushu Prefecture, including Nangqian, Chindu, Yushu, Zadoi, Qumarlêb, and Zhiduo. Drinking water samples and 10 brick tea samples were collected from each village to determine the fluoride content in water and brick tea; at least 100 permanent residents aged ≥ 25, who had a habit of drinking brick tea and had lived in the local area for more than 5 years, were selected for X-ray imaging to examine the prevalence of adult skeletal fluorosis.Results:A total of 75 samples of residential drinking water were collected, with a fluoride content of (0.21 ± 0.05) mg/L, ranging from 0.11 to 0.34 mg/L; 60 samples of brick tea, with a fluoride content of (626.70 ± 157.27) mg/kg, ranging from 324.00 to 2 102.00 mg/kg. A total of 1 136 adults were examined, and 318 cases of skeletal fluorosis were diagnosed, with a detection rate of 27.99%. Among them, the detection rates of mild, moderate, and severe skeletal fluorosis were 20.95% (238/1 136), 6.07% (69/1 136), and 0.97% (11/1 136), respectively, with mild symptoms being the main. The detection rates of skeletal fluorosis in males and females were 29.09% (121/416) and 27.36% (197/720), respectively, with no statistically significant difference between the gender (χ 2 = 0.39, P = 0.533). Comparison of the skeletal fluorosis in different gender, the differences were statistically significant (χ 2 = 22.31, P < 0.001). The detection rates of skeletal fluorosis in the age groups of 25 - 35, 36 - 45, 46 - 55, 56 - 65, 66 - 75, and ≥76 years old were 6.86% (7/102), 22.37% (51/228), 24.02% (92/383), 37.44% (73/195), 43.48% (70/161), and 37.31% (25/67), respectively. The differences between the groups were statistically significant (χ 2 = 59.84, P < 0.001). Moreover, there was a statistically significant difference in the composition of skeletal fluorosis among different age groups ( H = 37.66, P < 0.001). The Spearman correlation analysis results showed that the severity of adult skeletal fluorosis was positively correlated with age ( r = 0.34, P < 0.001). Conclusions:There is a certain degree of prevalence of adult skeletal fluorosis in Yushu Prefecture. And as age increases, the condition of skeletal fluorosis becomes more severe.
3.Aspiration after dysphasia in recent twenty years:a visualized analysis
Longxian HUANG ; Yan ZUO ; Limei CHEN ; Sijia GU ; Jinmei JIANG ; Zhiwei ZHANG
Chinese Journal of Rehabilitation Theory and Practice 2024;30(3):292-302
Objective To analyze the current status,hot spots and trends of Chinese and English researches in the field of aspiration after dysphasia in the past twenty years. Methods The articles about aspiration after dysphasia were retrieved from CNKI and Web of Science(WOS)core collec-tion database,from January,2003 to June,2023,and were analyzed with CiteSpace 6.1.R6. Results A total of 3 231 articles were included.The annual articles were published more and more year by year.The most English literatures came from the United States.Hot spots mainly focused on the assessment of dysphasia,prevention of complication,nutrition and rehabilitation therapy.It would concentrate on the application of the volume-viscosity swallow test and assessment scales,rehabilitation,penetration aspiration,outcome and effect validation,quality of life,feeding and nutrition condition,and evidence-based nursing,etc.,in the future. Conclusion The researches in the field of aspiration after dysphasia have been increasing in recent years,and the themes and contents of researches have been deepening.
4.Bibliometric analysis on research about low-level occupational benzene exposure
Danping DUAN ; Shuzhen BAI ; Yingyin LIU ; Luxi BAI ; Jinmei LIANG ; Ling ZHU ; Lin CHEN ; Huidong SONG ; Xuemei CHEN ; Zhi WANG
China Occupational Medicine 2024;51(2):199-204
ObjectiveTo analyze the research status and trends in low-level occupational benzene exposure. Methods Articles on low-level occupational benzene exposure from Chinese and English journals from January 1st, 2000, to December 31th, 2022 were retrieved using the Web of Science and the China National Knowledge Infrastructure, and a bibliometric analysis was conducted. Results A total of 327 articles were included in the analysis, comprising 216 English articles and 111 Chinese articles. i) The number of articles published in English fluctuates greatly over the years, without a trend of continuous growth or decline. Authors from 359 research institutions in 45 countries and regions have published relevant English articles in 97 kinds of journals, involving 281 grants from 226 foundations. The top three countries in terms of articles amount were the United States, Italy, and China, with 81, 46, and 43 papers, respectively. The English articles mainly focused on mechanistic research at the genetic level, such as hematotoxicity, oxidative stress, and DNA damage. ii) The number of Chinese articles increased gradually after 2012, with the growth peak in 2017. Authors from 127 research institutions in 26 provinces, autonomous regions, and municipalities published Chinese articles in 51 kinds of journals, involving 154 grants from 78 foundations. Chinese articles tended to focus on benzene-induced hematotoxicity and occupational health damage. Conclusion Most studies on low-level occupational benzene exposure were conducted in China, the United States and Italy, focused on hematotoxicity. Monitoring international research topics and hotspots of the field has certain reference value for related research in China.
5.Effect and mechanism of miR-155-5p on myocardial ischemia-reperfusion injury in rats by regulating myocardial pyroptosis
Qiuyu LU ; Yanqing CHEN ; Qingrong SHEN ; Xin LI ; Bingyu XIA ; Jinmei SU
Organ Transplantation 2024;15(6):903-911
Objective To explore the effect and mechanism of microRNA(miR)-155-5p on myocardial pyroptosis in rats with myocardial ischemia-reperfusion injury(IRI).Methods Sixty SD rats were randomly divided into sham group,IRI group,agomir-NC group,miR-155-5p agomir group,antagomir-NC group,and miR-155-5p antagomir group,with 10 rats in each group.Echocardiography was used to measure the left ventricular end-diastolic diameter(LVEDD),left ventricular end-systolic diameter(LVESD),left ventricular ejection fraction(LVEF),and left ventricular fractional shortening(LVFS)of rats.Enzyme-linked immune absorbent assay(ELISA)was used to detect the levels of creatine kinase isoenzyme(CK-MB),lactate dehydrogenase(LDH),and cardiac troponin T(cTnT)in serum,as well as the levels of interleukin(IL)-1β,IL-6,IL-18,and tumor necrosis factor(TNF)-α in myocardial tissue of rats.Hematoxylin-eosin staining was used to observe pathological changes in rat myocardial tissue.Real-time fluorescent quantitative polymerase chain reaction was used to detect the expression levels of miR-155-5p and silent information regulator 1(SIRT1)messenger RNA(mRNA)in myocardial tissue of rats.Dual-luciferase reporter gene assay was used to verify the targeting relationship between miR-155-5p and SIRT1.Western blot was used to detect the expression levels of SIRT1,NOD-like receptor protein 3(NLRP3),cleaved cysteine aspartate specific proteinase-1(Cleaved Caspase-1),and gasdermin D(GSDMD)proteins in myocardial tissue of rats.Results Compared with the sham group,the LVEDD and LVESD of rats in the IRI group were increased,LVEF and LVFS were decreased,serum levels of CK-MB,LDH,and cTnT were increased,IL-1β,IL-6,IL-18 and TNF-α levels in myocardial tissue were increased,myocardial tissue structure was severely damaged,myocardial fibers were disordered,relative expression of NLRP3,Cleaved Caspase-1,and GSDMD proteins were increased,and the relative expression of SIRT1 protein was decreased(all P<0.05/5).Compared with the IRI group,the rats in the miR-155-5p agomir group had increased LVEDD and LVESD,decreased LVEF and LVFS,increased serum levels of CK-MB,LDH,and cTnT,increased myocardial tissue levels of IL-1β,IL-6,IL-18,TNF-α,aggravated myocardial tissue lesions,increased relative expression of NLRP3,Cleaved Caspase-1,and GSDMD proteins,and decreased relative expression of SIRT1 protein,and the rats in the miR-155-5p antagomir group had decreased LVEDD and LVESD,increased LVEF and LVFS,decreased serum levels of CK-MB,LDH,and cTnT,decreased myocardial tissue levels of IL-1β,IL-6,IL-18,TNF-α,reduced myocardial tissue lesions,decreased relative expression of NLRP3,Cleaved Caspase-1,and GSDMD proteins,and increased relative expression of SIRT1 protein(all P<0.05/5).miR-155-5p was negatively correlated with the expression levels of SIRT1 in rat myocardial tissue,and SIRT1 was a target gene of miR-155-5p.Conclusions miR-155-5p may participate in the regulation of myocardial IRI in rats by targeting the downregulation of SIRT1 and promoting NLRP3-mediated myocardial pyroptosis.
6.Expression of connexin 43 in hippocampus of post-stroke depression model rats and its effect on cell apoptosis
Jinmei CHEN ; Yu WANG ; Jie WANG ; Xuelian LUO ; Gongjun WANG ; Chengzheng BAO ; Xuebin LI
Chinese Journal of Behavioral Medicine and Brain Science 2024;33(6):487-493
Objective:To explore the expression of connexin 43 (Cx43) in hippocampus of post-stroke depression (PSD) model rats and its effect on cell apoptosis and depressive-like behavior.Methods:Sixty SPF-grade male SD rats aged 6-8 weeks were randomly divided into five groups (12 rats in each group): normal group, stroke group, depression group, PSD group and carbenoxolone(CBX) group. The stroke model was established by injection of endothelin-1.Chronic unpredictable mild stress (CUMS) combined with solitary rearing was used to establish a depression model. Rats in PSD group were given CUMS and raised alone on the seventh day of stroke modeling.Rats in CBX group were given intraperitoneal injection of CBX(20 mg/kg) on 14th day after PSD modeling. The depressive-like behavior of rats was evaluated by sugar water preference test and open field test. The expression of Cx43 mRNA in hippocampus of rats was detected by RT-PCR, the expression levels of Cx43, caspase-3, Bax and Bcl-2 were detected by Western blot, and the changes of apoptosis rate were detected by TUNEL staining. SPSS 23.0 software was used for statistical analysis, the behavioral data were analyzed by repeated measurement ANOVA, the remaining data were analyzed by one-way ANOVA, and the LSD- t test was used for further pairwise comparison. Results:(1)As for the preference rate of sugar water and the times of crossing the grid, the interaction effects between time and group were significant among the 5 groups( Finteraction=35.57, 111.43, both P<0.05). On the 28th day after operation, the preference rate of sugar water and the times of crossing grid in depression group and PSD group were lower than those in stroke group (all P<0.05), while the preference rate of sugar water and the times of crossing grid in CBX group were both lower than those in PSD group (both P<0.05). (2) The levels of Cx43 mRNA and Cx43 protein in the five groups were significantly different ( F=273.57, 64.56, both P<0.05). The levels of Cx43 mRNA and Cx43 protein in depression group ((0.59±0.05), (0.69±0.08)) and PSD group ((0.61±0.07), (0.63±0.12)) were lower than those in stroke group ((1.01±0.03), (1.05±0.08)) (all P<0.05). The levels of Cx43 mRNA and Cx43 protein in CBX group ((0.30±0.01), (0.37±0.09)) were lower than those in PSD group (both P<0.05). (3) The protein levels of caspase-3, Bax, Bcl-2 and Bcl-2/Bax and the apoptosis rate of the five groups were significantly different ( F=102.40, 90.27, 47.42, 159.99, 115.21, all P<0.05). The levels of caspase-3, Bax protein, apoptosis rate in stroke group ((0.44±0.06), (0.54±0.07), (29.16±5.03)) and depression group ((0.45±0.07), (0.59±0.09), (27.00±4.93)) were higher than those in normal group ((0.21±0.08), (0.33±0.07), (4.83±3.18)) (all P<0.05), the levels of Bcl-2 protein and Bcl-2/Bax in stroke group ((0.80±0.04), (1.51±0.20)) and depression group ((0.60±0.09), (1.03±0.09)) were lower than those in normal group ((1.04±0.13), (3.14±0.38)) (all P<0.05).The levels of caspase-3, Bax protein and apoptosis rate in PSD group ((0.76±0.05), (0.84±0.02), (44.50±3.83)) were all higher than those in stroke group and depression group (all P<0.05), and the levels of Bcl-2 protein and Bcl-2/Bax in PSD group ((0.50±0.14), (0.59±0.17)) were lower than those in stroke group and depression group (both P<0.05). The levels of caspase-3 and Bax protein and the apoptosis rate in CBX group ((1.03±0.10), (1.02±0.05), (56.00±4.81)) were higher than those in PSD group (all P<0.05).The levels of Bcl-2 protein and Bcl-2/Bax in CBX group((0.26±0.08), (0.25±0.08)) were lower than those in PSD group (both P<0.05). Conclusion:The expression level of Cx43 in the hippocampus of PSD model rats is downregulated, which can promote cell apoptosis and exacerbate depressive behavior.
7.In vitro study on the inhibition of hepatitis D virus replication by bulevirtide based on liver organoids
Le′er SHEN ; Jinmei CHEN ; Qingxin GUO ; Luying TIAN ; Xiaohua CHEN
Chinese Journal of Infectious Diseases 2024;42(3):160-166
Objective:To construct the liver organoid infected with hepatitis D virus (HDV), and to investigate the role of the sodium taurocholate cotransporting polypeptide (NTCP) receptor inhibitor bulevirtide in inhibiting viral replication.Methods:Hepatocyte-like cells (HLC) differentiated from induced pluripotent stem cells (iPSC) were seeded onto inverted colloidal crystal polyethylene glycol scaffolds (ICC) to construct liver organoids. After transfecting human hepatocelluar carcinoma cells (HuH7 cells) with plasmids, HDV particles were harvested from the supernatant, while HBV particles were extracted from the HepG2.2.15 cell supernatant. The liver organoids were infected with both HBV and HDV particles, and the negative control group without HDV infection was set up. The microstructure of the liver organoid units and the expression of hepatitis D antigen (HDAg) and hepatitis B surface antigen (HBsAg) were observed under laser scanning confocal microscope by immunofluorescence method. The protein levels of NTCP and HDAg in the liver organoids were detected by Western blotting. Bulevirtide was added before HDV infection (bulevirtide pre group) and 24 hours after infection (bulevirtide post group), and interferon-alpha (IFN-α) was also added after 24 hours infection (IFN-α group), and a control group without drug treatment was set up. HDV replication was compared among the four groups after drug intervention. Real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was used to measure the relative mRNA expression levels of Nanog homeobox (NANOG), sex determining region Y-box (SOX)2, SOX17, forkhead box protein A2 (FOXA2), hepatocyte nuclear factor 4 alpha (HNF-4α), albumin (ALB), alpha-fetoprotein (AFP), NTCP during the differentiation of iPSC, and the mRNA expression of HDV after the drug intervention of the four groups. Statistical analysis was performed using two independent sample t tests. Results:Within 21 days of the differentiation of iPSC into HLC, the mRNA expression level of NANOG gradually decreased, while the expression levels of SOX17, FOXA2 initially increased then decreased, and the expression levels of the HNF-4α, ALB, AFP and NTCP progressively increased. The protein level of NTCP in iPSC (0.118±0.003) was lower than that in HLC (1.315±0.073), and the difference was statistically significant ( t=11.92, P<0.001).The protein level of HDAg in the liver organoids after HDV infection was higher than that in the negative control group without HDV infection (1.284±0.128 vs 0.157±0.040), and the difference was statistically significant ( t=23.27, P<0.001).Laser scanning confocal microscopy showed three-dimensional spheroid structures and high expressions of HDAg and HBsAg at the 14th day of infection.Compared with the control group (1.000±0.077), the HDV mRNA expressions in both IFN-α group (0.453±0.028) and bulevirtide pre group (0.136±0.012) decreased after three days of drug intervention. The differences were statistically significant ( t=19.95 and 33.15, respectively, both P<0.001). However, there was no significant difference in HDV mRNA expressions between the bulevirtide post group (0.968±0.069) and the control group ( t=0.94, P>0.05). Conclusions:The liver organoids constructed from iPSC-derived HLC and ICC can simulate human liver functions and successfully be infected by HDV particles. Early blockade with bulevirtide can effectively reduce the level of viral replication in the HDV-infected liver organoids.
8.Effect of Lee-Silverman voice treatment on electroglottography parameters and speech function in Parkinson's disease patients with dysarthria
Chengju LIAO ; Jinmei PAN ; Shaobin CHEN ; Chenghong LUO ; Jian YANG ; Zhiqiang HUANG ; Jiaxing LUO ; Guiyang ZHANG ; Yuhan ZHANG
Chongqing Medicine 2024;53(9):1328-1332
Objective To explore the effect of Lee-Silverman voice treatment (LSVT) on language re-habilitation of dysarthria in Parkinson's disease (PD).Methods A total of 84 patients with PD dysarthria ad-mitted to our hospital from February 2019 to February 2022 were selected as the research objects.According to the random number table method,they were divided into observation group and control group,with 42 cases in each group.The control group received routine speech rehabilitation training,and the observation group re-ceived LSVT for four weeks.The scores of Western Aphasia Battery (WAB) and Aphasia Quotient (AQ) be-fore and after intervention were compared between the two groups,and the differences of electroglottographic parameters such as jitter,F0,shimmer,normalized noise energy (NNE) and harmonic noise ratio (HNR) were compared between the two groups.Results Before intervention,there was no significant difference in WAB scores (listening comprehension,repetition,spontaneous speech,naming) and AQ scores between the two groups (P>0.05).After intervention,the above scores of the two groups were significantly improved,and the observation group was higher than the control group,the difference was statistically significant (P<0.05). Before intervention,the jitter,F0,shimmer,NNE,HNR of vowels "a""i""u" in the two groups were not sta-tistically significant (P>0.05).After intervention,the above-mentioned electroglottic parameters of the two groups were significantly improved.The jitter and NNE of vowels "a""i""u" in the observation group were lower than those in the control group,and the HNR was higher than that in the control group,the differences were statistically significant (P<0.05).Conclusion LSVT can improve the electroglottographic parameters and speech function of patients with PD dysarthria,and the language rehabilitation effect of PD dysarthria is obvious.
9.Progress in clinical application of individualized exercise prescription based on threshold in metabolic syndrome
Feng WANG ; Ruojiang LIU ; Jinmei QIN ; Wenxue CHEN ; Zhiqiang PEI ; Weizhen XUE
Chinese Journal of Arteriosclerosis 2024;32(11):1006-1012
Patients with metabolic syndrome(MS)are at potential risk for cardiovascular disease and have received increasing public and medical attention.Studies have shown that regular physical exercise can effectively regulate meta-bolic indicators such as blood pressure,blood sugar and blood lipids,and play a positive role in reducing the risk of cardio-vascular disease and improving the prognosis of patients.Exercise intensity has been identified as the most important as-pect in reducing the risk of cardiovascular death and all-cause mortality in exercise intervention.Therefore,the design of exercise prescription which is both scientific and satisfying individual differences has become the focus of research.Most of the current clinical studies are based on the percentage of exercise intensity as the basis for the formulation of standard-ized exercise prescription for MS patients,while the studies on the individualized threshold of exercise intensity based on cardiopulmonary exercise test(CPET)are still few.CPET has shown that individualized exercise prescription can effec-tively reduce body composition index,blood pressure and blood glucose,improve cardiorespiratory function,exercise en-durance and quality of life in MS patients.This paper reviewed the development of individualized exercise programs with different intensification according to threshold indexes in CPET,analyzed the intervention effects and possible mechanisms for MS patients and subgroups,and provided certain reference for the formulation and implementation of personalized exer-cise prescriptions for MS patients,and also provided references for in-depth research on individualized exercise intervention for MS.
10.Polysomnography and Neuropsychological Analysis of Patients With Post-Traumatic Stress Disorder Two Years After the COVID-19 Pandemic in Wuhan
Junhua MEI ; Yanjie XU ; Xue GONG ; Jinmei XU ; Guohua CHEN ; Weiqi CHEN ; Yicong WANG ; Zhaohong KONG ; Yilong WANG ; Qing YANG
Psychiatry Investigation 2024;21(3):219-229
Objective:
We used polysomnography (PSG) monitoring and neuropsychological scales to explore the characteristics of coronavirus disease-2019 (COVID-19) patients diagnosed with post-traumatic stress disorder (PTSD) in Wuhan, two years after the onset of the COVID-19 pandemic.
Methods:
A total of 42 patients in the Sleep Medicine Center were diagnosed with insomnia between December 2021 and May 2022; they were divided into the PTSD group (patients with PTSD diagnosed with insomnia after COVID-19 infection) and the non-PTSD group (patients with insomnia without PTSD). A healthy control group was simultaneously included.
Results:
The PTSD group was more significant than the non-PTSD group in partial manifestations of sleep disorders, neuropsychological clinical symptoms, and partial PSG data. Patients with different COVID-19 subtypes showed significant differences in the course of disease, sleep disorders, neuropsychological clinical symptoms, relevant scale scores, and PSG data analysis.
Conclusion
The emotional anxiety and depression of COVID-19 patients diagnosed with PTSD two years after the COVID-19 pandemic in Wuhan are more significant, and will not be self-alleviated with the passage of time. It is necessary to continue to pay attention to the PTSD symptoms and sleep psychology of COVID-19 infected patients, and take appropriate measures. Patients with severe and critical COVID-19 have more severe sleep and mental disorders, and there is a significant correlation between the duration of the disease and the severity of mental and mental disorders and sleep disorders after recovery.

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