1.Effects of electroacupuncture on cognitive impairment and mitophagy mediated by KIF5A/Miro1 pathway in Parkinson's disease mice.
Mengzhu LI ; Jiafan CHEN ; Mengxuan CHEN ; Haiyan LI ; Zhenyi ZHANG ; Da GAO ; Weicong ZENG ; Lijun ZHAO ; Meiling ZHU
Chinese Acupuncture & Moxibustion 2025;45(8):1111-1119
OBJECTIVE:
To explore the improvement effect of electroacupuncture (EA) based on Xingnao Kaiqiao acupuncture (acupuncture for regaining consciousness and opening orifices) on cognitive impairment in mice with Parkinson's disease (PD), and to explore its regulatory mechanisms on the kinesin family member 5A (KIF5A)/mitochondrial Rho GTPase 1 (Miro1) pathway and mitophagy in prefrontal cortical neurons.
METHODS:
A total of 70 male C57BL/6J mice of clean grade were randomly divided into a normal group (12 mice), a sham operation group (12 mice), and a model pre-screening group (46 mice). Unilateral stereotaxic injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle was adopted to establish the PD model in the model pre-screening group. Twenty-four mice after successful modeling were randomly selected and divided into a model group and an EA group, 12 mice in each one. In the EA group, acupuncture was applied at "Shuigou" (GV26) and bilateral "Sanyinjiao" (SP6) and "Neiguan" (PC6), ipsilateral "Sanyinjiao" (SP6) and "Neiguan" (PC6) were connected to EA respectively, with disperse-dense wave, 5 Hz/20 Hz in frequency, 0.5 mA in current intensity, 20 min a time, 6 times a week for 30 days. Cognitive function was assessed by Y-maze and Morris water maze tests; morphology of prefrontal cortex was observed by H.E. staining; reactive oxygen species (ROS) level in prefrontal cortex was detected by fluorescence probe method; mitochondrial morphology and autophagosome ultrastructure were observed by transmission electron microscopy; the mRNA expression of tyrosine hydroxylase (TH) was detected by quantitative real-time PCR; the protein expression of TH, KIF5A, Miro1, p62, Parkin and PTEN induced kinase 1 (PINK1) was detected by Western blot.
RESULTS:
Compared with the sham operation group, both the model group and the EA group exhibited increased rotation number of per minute (P<0.001). Compared with the sham operation group, in the model group, the novel arm exploration time of Y-maze test was shortened (P<0.001), the escape latency of Morris water maze test was prolonged (P<0.05) and the platform crossing number of Morris water maze test was reduced (P<0.01); in the prefrontal cortex, the number of cellular vacuole and neurons with karyopyknosis was increased (P<0.001), and mitochondrial autophagosomes could be observed; in the prefrontal cortex, the relative expression of ROS was increased (P<0.001), the protein and mRNA expression of TH was decreased (P<0.001), the protein expression of Miro1, PINK1, Parkin was increased (P<0.001, P<0.01), the protein expression of KIF5A and p62 was decreased (P<0.001). Compared with the model group, in the EA group, the novel arm exploration time of Y-maze test was prolonged (P<0.01), the escape latency of Morris water maze test was shortened (P<0.05) and the platform crossing number of Morris water maze test was increased (P<0.05); in the prefrontal cortex, the number of cellular vacuole and neurons with karyopyknosis was decreased (P<0.001), and the number of mitochondrial autophagosomes reduced and the mitochondrial morphology was improved; in the prefrontal cortex, the relative expression of ROS was decreased (P<0.01), the protein and mRNA expression of TH was increased (P<0.001, P<0.01), the protein expression of Miro1, PINK1, Parkin was decreased (P<0.001, P<0.01, P<0.05), the protein expression of KIF5A and p62 was increased (P<0.01, P<0.05).
CONCLUSION
Xingnao Kaiqiao electroacupuncture effectively alleviates cognitive impairment and damage of neuronal function in PD mice, its mechanism may be related to the regulation of KIF5A/Miro1 pathway, hence reducing the mitophagy in prefrontal cortical neurons.
Animals
;
Electroacupuncture
;
Male
;
Mice
;
Parkinson Disease/physiopathology*
;
Cognitive Dysfunction/psychology*
;
Kinesins/genetics*
;
Humans
;
Mitophagy
;
Mice, Inbred C57BL
;
rho GTP-Binding Proteins/genetics*
;
Mitochondria/genetics*
;
Prefrontal Cortex/metabolism*
2.Analysis of a child with X-linked intellectual disability type 100 due to variant of KIF4A gene and a literature review.
Xiaoxuan FAN ; Zhengfang CHEN ; Xiaoyan XUAN ; Xiaoke ZHAO
Chinese Journal of Medical Genetics 2025;42(10):307-313
OBJECTIVE:
To explore the clinical phenotype and variants of KIF4A gene associated with X-linked intellectual disability type 100 (XLID100) in a child by whole-exome sequencing (WES).
METHODS:
A child presented at the Children's Hospital Affiliated to Nanjing Medical University in September 2023 was selected as the study subject. Clinical data of the child was retrospectively analyzed. Peripheral blood samples were collected from the child and his family members for WES analysis. Candidate variant was verified by Sanger sequencing. Pathogenicity of the candidate variant was rated based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). The variant was also searched in dbSNP, OMIM, HGMD, ClinVar and gnomAD databases. Amino acid sequences of the KIF4A protein across various species were retrieved from the Ensembl Genome Browser Database and analyzed using Clustal Omega software. Relevant literature on KIF4A gene mutations associated with XLID100 was reviewed. This study has been approved by the Medical Ethics Committee of the Hospital (Ethics No. 202402022-1).
RESULTS:
The child, a 3-year-6-month-old male, had manifested intellectual impairment, language delay, autism, and choroid cyst revealed by cranial magnetic resonance imaging. No facial dysmorphism, tooth anomaly, gross motor development delay or regression, and history of seizure and febrile convulsion was noted. WES revealed that he has harbored a c.3385delinsTATC (p.Thr1129delinsTyrPro) variant of the KIF4A gene. Sanger sequencing confirmed that his mother and sister have harbored the same variant, whilst his father was of the wild type. Both of his parents had a normal phenotype. The variant was classified as of uncertain significance based on the guidelines from the ACMG. It was not recorded by the dbSNP, OMIM, HGMD, ClinVar and the gnomAD database. Conservative analysis suggested that the variant site, which normally encodes a cysteine, is highly conserved among various species. A review of the literature had retrieved 6 relevant articles documenting a total of 27 cases of KIF4A gene mutations, with only one case from China.
CONCLUSION
The c.3385delinsTATC (p.Thr1129delinsTyrPro) variant of the KIF4A gene probably underlay the XLID100 in this child. Above finding has provided a reference for the clinical diagnosis and genetic counseling and enriched the mutation spectrum of the KIF4A gene.
Humans
;
Kinesins/genetics*
;
Male
;
Child, Preschool
;
Intellectual Disability/genetics*
;
Mutation
;
Exome Sequencing
;
X-Linked Intellectual Disability/genetics*
;
Phenotype
3.Clinical phenotype and genetic analysis of a child with Progressive familial intrahepatic cholestasis type 8 due to compound heterozygous variants of KIF12 gene.
Xiaoying ZHOU ; Jun ZHANG ; Wenting ZHANG
Chinese Journal of Medical Genetics 2025;42(9):1132-1140
OBJECTIVE:
To explore the clinical manifestation and genotype of a child with Progressive familial intrahepatic cholestasis 8 (PFIC8) due to variant of KIF12 gene.
METHODS:
A child diangosed with PFIC8 at Changzhou Children's Hospital in October 2017 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples (3 mL each) were collected from the patient, her parents and younger sister. Following extraction of genomic DNA, whole exome sequencing (WES) was carried out. Candidate variants were validated using Sanger sequencing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the pathogenicity of candidate variants was classified. This study has been approved by the Medical Ethics Committee of Changzhou Children's Hospital (Ethics No.: 2023-002).
RESULTS:
The main clinical manifestations of the child included high GGT cholestasis, portal hypertension, splenomegaly, and abnormal liver enzymes. WES revealed that she has harbored compound heterozygous variants of the KIF12 gene, namely c.245G >A (p.Arg82Gln) and c.1291del (p.Ser431Valfs*13). Bioinformatics analyses showed that both variants were pathogenic. A total of 25 cases were reported in 7 English literature, including 13 males and 12 females. All patients had presented with high GGT cholestasis. Some had progressed to cirrhosis, and 3 cases also had renal lesions. No death was reported. Six children were treated with LTx. Nineteen children were found to harbor homozygous variants of the KIF12 gene, and the remaining six harbored compound heterozygous variants of the same gene. The most common mutation was c.655C>T (p.Arg219*). The mutation sites are mainly located in the Kinesin motor catalytic domain, with high GGT cholestasis as the main clinical feature. No correlation was found between the genotype and phenotype.
CONCLUSION
PFIC8 caused by KIF12 deficiency is mainly characterized by high GGT cholestasis, for which there is no effective treatment. The c.245G>A and c.1291del compound heterozygous variants of the KIF12 gene probably underlay the pathogenesis in this child.
Humans
;
Kinesins/genetics*
;
Female
;
Cholestasis, Intrahepatic/genetics*
;
Phenotype
;
Heterozygote
;
Child
;
Mutation
;
Child, Preschool
;
Male
;
Exome Sequencing
4.Clinical features and genetic analysis of a child with Progressive familial intrahepatic cholestasis type 8 due to compound heterozygous variants of KIF12 gene.
Dayan SUN ; Shixuan ZHANG ; Junmin LIAO ; Shuangshuang LI ; Dingding WANG ; Ya'nan ZHANG ; Yichao GU ; Kaiyun HUA ; Jinshi HUANG ; Yong ZHAO
Chinese Journal of Medical Genetics 2025;42(12):1437-1445
OBJECTIVE:
To explore the clinical phenotype and genetic characteristics of a child with Progressive familial intrahepatic cholestasis type 8 (PFIC8). METHODS A child with PFIC diagnosed at Beijing Children's Hospital Affiliated to Capital Medical University in September 2025 was selected as the study subject. Peripheral venous blood samples were collected from the child and her parents. Following extraction of genomic DNA, whole-exome sequencing (WES) was carried out. Candidate variants were validated by Sanger sequencing. The pathogenicity of the candidate variants was classified based on the guidelines from American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of Beijing Children's Hospital Affiliated to Capital Medical University (Ethics No.: 2023-E-126-Y).
RESULTS:
The proband, a 2-month-old female infant, had manifested jaundice of the skin and sclera, and slightly distended abdomen. She had no visible abdominal wall varicose veins, soft abdomen, and no palpable masses. Biliary atresia was ruled out by intraoperative cholangiography. WES revealed that she has harbored compound heterozygous variants of KIF12 gene, namely c.809C>T (p.Ala270Val) and c.1313G>A (p.Arg438Lys), which were verified by Sanger sequencing to have derived from her mother and father, respectively. According to the ACMG guidelines, both variants were classified as variants of uncertain significance (VUS). Based on the pre-defined search strategy, 10 articles were retrieved, which involved 25 PFIC cases, including 5 from China. Together with the proband of this study, the 26 PFIC patients have primarily presented with high GGT cholestasis, with the genetic cause in all cases attributed to variants of the KIF12 gene.
CONCLUSION
The c.809C>T and c.1313G>A compound heterozygous variants of the KIF12 gene probably underlay the pathogenesis of cholestatic liver disease in this child. Above findings have enriched the mutational and phenotypic spectra of PFIC8.
Humans
;
Kinesins/genetics*
;
Female
;
Cholestasis, Intrahepatic/genetics*
;
Infant
;
Heterozygote
;
Mutation
;
Exome Sequencing
;
Male
5.RGS12 represses oral squamous cell carcinoma by driving M1 polarization of tumor-associated macrophages via controlling ciliary MYCBP2/KIF2A signaling.
Gongsheng YUAN ; Shuting YANG ; Shuying YANG
International Journal of Oral Science 2023;15(1):11-11
Tumor-associated macrophages (TAMs) play crucial roles in tumor progression and immune responses. However, mechanisms of driving TAMs to antitumor function remain unknown. Here, transcriptome profiling analysis of human oral cancer tissues indicated that regulator of G protein signaling 12 (RGS12) regulates pathologic processes and immune-related pathways. Mice with RGS12 knockout in macrophages displayed decreased M1 TAMs in oral cancer tissues, and extensive proliferation and invasion of oral cancer cells. RGS12 increased the M1 macrophages with features of increased ciliated cell number and cilia length. Mechanistically, RGS12 associates with and activates MYC binding protein 2 (MYCBP2) to degrade the cilia protein kinesin family member 2A (KIF2A) in TAMs. Our results demonstrate that RGS12 is an essential oral cancer biomarker and regulator for immunosuppressive TAMs activation.
Mice
;
Humans
;
Animals
;
Tumor-Associated Macrophages/metabolism*
;
Carcinoma, Squamous Cell
;
Squamous Cell Carcinoma of Head and Neck
;
Mouth Neoplasms
;
GTP-Binding Proteins/metabolism*
;
Head and Neck Neoplasms
;
Ubiquitin-Protein Ligases/metabolism*
;
Adaptor Proteins, Signal Transducing/metabolism*
;
RGS Proteins/metabolism*
;
Kinesins/metabolism*
;
Repressor Proteins/metabolism*
6.Analysis of KIF1A gene variant in a Chinese pedigree affected with Spastic paraplegia type 30.
Gang XU ; Jianwei LI ; Zhanjin DENG ; Yuan XIA ; Tao WANG ; Yan BAI ; Yan QI ; Yong An ZHOU
Chinese Journal of Medical Genetics 2023;40(4):419-422
OBJECTIVE:
To explore the genetic basis for a Chinese pedigree affected with hereditary spastic paraplegia type 30 (HSP30).
METHODS:
A proband presented at the Second Hospital of Shanxi Medical University in August 2021 was selected as the study subject. The proband was subjected to whole exome sequencing, and candidate variant was verified by Sanger sequencing and bioinformatic analysis.
RESULTS:
The proband was found to have harbored a heterozygous c.110T>C variant in exon 3 of the KIF1A gene, which can cause substitution of isoleucine by threonine at position 37 (p.I37T) and alter the function of its protein product. The same variant was not found in his parents, elder brother and elder sister, suggesting that it has a de novo origin. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), the variant was rated as likely pathogenic (PM2_Supporting+PP3+PS2).
CONCLUSION
The c.110T>C variant of the KIF1A gene probably underlay the HSP30 in the proband. Above finding has enable genetic counseling for this family.
Humans
;
Male
;
East Asian People
;
Kinesins/genetics*
;
Mutation
;
Pedigree
;
Spastic Paraplegia, Hereditary/genetics*
;
Female
7.Autosomal dominant neurodevelopmental disorders associated with KIF1A gene variants in 6 pediatric patients.
Jingqi LIN ; Niu LI ; Ru'en YAO ; Tingting YU ; Xiumin WANG ; Jian WANG
Journal of Zhejiang University. Medical sciences 2023;52(6):693-700
OBJECTIVES:
To analyze the clinical and genetic characteristics of children with autosomal dominant neurodevelopmental disorders caused by kinesin family member 1A (KIF1A) gene variation.
METHODS:
Clinical and genetic testing data of 6 children with KIF1A gene de novo heterozygous variation diagnosed in Shanghai Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine from the year 2018 to 2020 were retrospectively analyzed. Pathogenic variants were identified based on whole exome sequencing, and verified by Sanger sequencing. Moreover, the effect of variants on three-dimensional structure and stability of protein was analyzed by bioinformatics.
RESULTS:
Among 6 patients there were 4 males and 2 females, and the age of consultation varied from 7 months to 18 years. All cases had varying degrees of motor developmental delay since childhood, and 4 of them had gait abnormalities or fell easily. In addition, 2 children were accompanied by delayed mental development, epilepsy and abnormal eye development. Genetic tests showed that all 6 cases had heterozygous de novo variations of KIF1A gene, including 4 missense mutations c.296C>T (p.T99M), c.761G>A (p.R254Q), c.326G>T (p.G109V), c.745C>G (p.L249V) and one splicing mutation c.798+1G>A, among which the last three variants have not been previously reported. Bioinformatics analysis showed that G109V and L249V may impair their interaction with the neighboring amino acid residues, thereby impacting protein function and reducing protein stability, and were assessed as "likely pathogenic". Meanwhile, c.798+1G>A may damage an alpha helix in the motor domain of the KIF1A protein, and was assessed as "likely pathogenic".
CONCLUSIONS
KIF1A-associated neurological diseases are clinically heterogeneous, with motor developmental delay and abnormal gait often being the most common clinical features. The clinical symptoms in T99M carriers are more severe, while those in R254Q carriers are relatively mild.
Male
;
Female
;
Humans
;
Child
;
Retrospective Studies
;
China
;
Mutation
;
Epilepsy/genetics*
;
Neurodevelopmental Disorders/genetics*
;
Kinesins/genetics*
8.Double heterozygous pathogenic mutations in KIF3C and ZNF513 cause hereditary gingival fibromatosis.
Jianfan CHEN ; Xueqing XU ; Song CHEN ; Ting LU ; Yingchun ZHENG ; Zhongzhi GAN ; Zongrui SHEN ; Shunfei MA ; Duocai WANG ; Leyi SU ; Fei HE ; Xuan SHANG ; Huiyong XU ; Dong CHEN ; Leitao ZHANG ; Fu XIONG
International Journal of Oral Science 2023;15(1):46-46
Hereditary gingival fibromatosis (HGF) is a rare inherited condition with fibromatoid hyperplasia of the gingival tissue that exhibits great genetic heterogeneity. Five distinct loci related to non-syndromic HGF have been identified; however, only two disease-causing genes, SOS1 and REST, inducing HGF have been identified at two loci, GINGF1 and GINGF5, respectively. Here, based on a family pedigree with 26 members, including nine patients with HGF, we identified double heterozygous pathogenic mutations in the ZNF513 (c.C748T, p.R250W) and KIF3C (c.G1229A, p.R410H) genes within the GINGF3 locus related to HGF. Functional studies demonstrated that the ZNF513 p.R250W and KIF3C p.R410H variants significantly increased the expression of ZNF513 and KIF3C in vitro and in vivo. ZNF513, a transcription factor, binds to KIF3C exon 1 and participates in the positive regulation of KIF3C expression in gingival fibroblasts. Furthermore, a knock-in mouse model confirmed that heterozygous or homozygous mutations within Zfp513 (p.R250W) or Kif3c (p.R412H) alone do not led to clear phenotypes with gingival fibromatosis, whereas the double mutations led to gingival hyperplasia phenotypes. In addition, we found that ZNF513 binds to the SOS1 promoter and plays an important positive role in regulating the expression of SOS1. Moreover, the KIF3C p.R410H mutation could activate the PI3K and KCNQ1 potassium channels. ZNF513 combined with KIF3C regulates gingival fibroblast proliferation, migration, and fibrosis response via the PI3K/AKT/mTOR and Ras/Raf/MEK/ERK pathways. In summary, these results demonstrate ZNF513 + KIF3C as an important genetic combination in HGF manifestation and suggest that ZNF513 mutation may be a major risk factor for HGF.
Animals
;
Humans
;
Mice
;
Fibromatosis, Gingival/pathology*
;
Gingiva
;
Kinesins/genetics*
;
Mutation/genetics*
;
Phosphatidylinositol 3-Kinases/genetics*
9.Primary lung adenocarcinoma complicated with lung hamartoma: A case report and literature review.
Li WANG ; Liang ZHOU ; Jianyong ZHANG
Journal of Central South University(Medical Sciences) 2022;47(4):529-534
The clinical data for a patient with primary lung adenocarcinoma complicated with pulmonary hamartoma, who admitted to Zunyi Medical University Hospital in September 2020, was retrospectively analyzed. The 62-years-old male visited outpatient service because of dysphagia in March 2015, and the pulmonary nodules were found. In September 2020, the computed tomography indicated the enlarged nodule in the lower lobe of left lung with lobulation, and there was ground glass nodule in the upper lobe of left lung. After thoracoscopic wedge surgery, the primary pulmonary adenocarcinoma in the upper lobe of left lung and pulmonary hamartoma in the lower lobe of left lung were confirmed by pathology. Whole exon sequencing revealed that kinesin family member 20B (KIF20B) gene was not expressed in lung adenocarcinoma, but was expressed in pulmonary hamartoma. The clinical manifestations of lung adenocarcinoma complicated with pulmonary hamartoma was not typical, which could locate in the same side and different sides of the lung. The imaging manifestations of the 2 kinds of tumors were diverse and can not be completely distinguished. The pathological examination after surgery is the gold standard, and the possibility of malignant transformation of pulmonary hamartoma should be warned.
Adenocarcinoma of Lung/complications*
;
Hamartoma/surgery*
;
Humans
;
Kinesins
;
Lung/pathology*
;
Lung Neoplasms/surgery*
;
Male
;
Middle Aged
;
Retrospective Studies
10.Genetic distribution in Chinese patients with hereditary peripheral neuropathy.
Xiao Xuan LIU ; Xiao Hui DUAN ; Shuo ZHANG ; A Ping SUN ; Ying Shuang ZHANG ; Dong Sheng FAN
Journal of Peking University(Health Sciences) 2022;54(5):874-883
OBJECTIVE:
To analyze the distribution characteristics of hereditary peripheral neuropathy (HPN) pathogenic genes in Chinese Han population, and to explore the potential pathogenesis and treatment prospects of HPN and related diseases.
METHODS:
Six hundred and fifty-six index patients with HPN were enrolled in Peking University Third Hospital and China-Japan Friendship Hospital from January 2007 to May 2022. The PMP22 duplication and deletion mutations were screened and validated by multiplex ligation probe amplification technique. The next-generation sequencing gene panel or whole exome sequencing was used, and the suspected genes were validated by Sanger sequencing.
RESULTS:
Charcot-Marie-Tooth (CMT) accounted for 74.3% (495/666) of the patients with HPN, of whom 69.1% (342/495) were genetically confirmed. The most common genes of CMT were PMP22 duplication, MFN2 and GJB1 mutations, which accounted for 71.3% (244/342) of the patients with genetically confirmed CMT. Hereditary motor neuropathy (HMN) accounted for 16.1% (107/666) of HPN, and 43% (46/107) of HPN was genetically confirmed. The most common genes of HMN were HSPB1, aminoacyl tRNA synthetases and SORD mutations, which accounted for 56.5% (26/46) of the patients with genetically confirmed HMN. Most genes associated with HMN could cause different phenotypes. HMN and CMT shared many genes (e.g. HSPB1, GARS, IGHMBP2). Some genes associated with dHMN-plus shared genes associated with amyotrophic lateral sclerosis (KIF5A, FIG4, DCTN1, SETX, VRK1), hereditary spastic paraplegia (KIF5A, ZFYVE26, BSCL2) and spinal muscular atrophy (MORC2, IGHMBP, DNAJB2), suggesting that HMN was a continuum rather than a distinct entity. Hereditary sensor and autosomal neuropathy (HSAN) accounted for a small proportion of 2.6% (17/666) in HPN. The most common pathogenic gene was SPTLC1 mutation. TTR was the main gene causing hereditary amyloid peripheral neuropathy. The most common types of gene mutations were p.A117S and p.V50M. The symptoms were characterized by late-onset and prominent autonomic nerve involvement.
CONCLUSION
CMT and HMN are the most common diseases of HPN. There is a large overlap between HMN and motor-CMT2 pathogenic genes, and some HMN pathogenic genes overlap with amyotrophic lateral sclerosis, hereditary spastic hemiplegia and spinal muscular atrophy, suggesting that there may be a potential common pathogenic pathway between different diseases.
Amyotrophic Lateral Sclerosis
;
Charcot-Marie-Tooth Disease/genetics*
;
DNA Helicases/genetics*
;
DNA-Binding Proteins/genetics*
;
Flavoproteins
;
HSP40 Heat-Shock Proteins
;
Humans
;
Intracellular Signaling Peptides and Proteins/genetics*
;
Kinesins
;
Ligases/genetics*
;
Molecular Chaperones
;
Multifunctional Enzymes
;
Muscular Atrophy, Spinal/genetics*
;
Mutation
;
Phosphoric Monoester Hydrolases
;
Protein Serine-Threonine Kinases
;
RNA Helicases/genetics*
;
RNA, Transfer
;
Transcription Factors/genetics*

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