1.Mechanistic Interplay Between Remodeling of The Peritubular Capillary Microenvironment and Renal Fibrosis
Qi-Fa QIN ; Wen-Hui HUANG ; Jun-Yue HUANG ; Guang-Run ZHANG ; Rong XUE ; Rui QIAN ; Li-Li XU ; Li-Ting DONG
Progress in Biochemistry and Biophysics 2026;53(10):2647-2664
Renal fibrosis is the common pathological endpoint of many forms of chronic kidney disease (CKD), yet the mechanisms determining effective repair versus persistent fibrotic remodeling remain incompletely understood. Peritubular capillaries (PTCs) are not merely passive targets of fibrotic injury, but form a dynamic vascular microenvironment linking regional perfusion, oxygen delivery, tubular metabolism, endothelial barrier integrity, pericyte support, immune-cell trafficking, and extracellular matrix (ECM) remodeling. We propose that PTC abnormalities should not be interpreted simply as reduced capillary density, but as a multidimensional disturbance of microvascular structure and function. Structural vascular preservation does not necessarily indicate effective microcirculation: anatomically detectable capillaries may still exhibit impaired perfusion, barrier dysfunction, abnormal endothelial-pericyte interactions, disturbed oxygen metabolism, or reduced network connectivity. Conversely, increased angiogenesis does not necessarily signify successful vascular repair if vessels remain immature, poorly perfused, or inadequately integrated into the existing network. To organize these abnormalities, we conceptualize PTC remodeling into four predominant but nonexclusive states: endothelial barrier disruption with inflammatory adhesion; endothelial-pericyte uncoupling with no-reflow; dysregulated angiogenesis with network simplification; and capillary rarefaction with fibrotic matrix locking. These states are not sequential stages of CKD. They may coexist within the same kidney, overlap within the same anatomical region, and vary with disease etiology, injury phase, vascular compartment, and treatment exposure. We further propose six dimensions for evaluating PTC status—structural presence, functional perfusion, barrier integrity, pericyte coupling, oxygen metabolism, and network connectivity—so that vascular quantity, function, and reparative capacity are assessed separately rather than inferred from a single endothelial marker or capillary-density measurement. Mechanistically, these states converge on a bidirectional microvascular-fibrotic feedback loop. Barrier disruption facilitates leukocyte recruitment and alters vascular paracrine signaling. Endothelial-pericyte uncoupling compromises capillary stability, whereas abnormal pericyte contraction may increase local vascular resistance and contribute to no-reflow before overt capillary loss. Dysregulated angiogenesis may generate vessels that fail to mature or connect to an effective perfusion network. Progressive capillary rarefaction compromises oxygen delivery, while sustained tubular transport demand and mitochondrial dysfunction may aggravate regional oxygen supply-demand mismatch. Injured tubules, immune cells, endothelial cells, pericytes, and fibroblasts communicate through soluble mediators, extracellular vesicles, direct cell contact, and cell-matrix signaling. Importantly, fibrosis is not merely a downstream consequence of microvascular injury. Altered ECM may increase diffusion distance, modify mechanotransduction, impair endothelial survival and migration, and restrict capillary reopening and regeneration. We use the term matrix locking to describe this sustained constraint on vascular repair, while emphasizing that current evidence does not establish irreversible disease in humans. This framework also has therapeutic implications. PTC-directed treatment should not be reduced to increasing vessel number or uniformly promoting angiogenesis. Instead, intervention should be matched to the dominant and potentially reversible abnormality: preserving endothelial barrier function; restoring endothelial-pericyte stability and reducing pathological microvascular resistance; normalizing angiogenesis so that vascular growth is accompanied by maturation, barrier competence, network integration, and effective perfusion; and, in advanced rarefaction, relieving matrix-related constraints while supporting vascular regeneration. The context- and time-dependent effects of signaling through VEGF, Tie2, PDGF-B/PDGFRβ, eNOS/NO, and related pathways indicate that the same molecular signal may exert different effects depending on disease context and timing. Therapeutic efficacy should therefore be evaluated by restoration of effective microcirculation and tissue function rather than by isolated molecular changes or capillary counts alone. Despite increasing mechanistic evidence, the translational basis for this framework remains limited. Most causal and interventional data derive from animal or cell models, whereas human evidence is largely limited to pathological observations, patient-sample associations, and prognostic studies. Currently available circulating and urinary candidate biomarkers generally lack sufficient specificity for PTC injury or state assignment, and no standardized quantitative thresholds have been externally validated. The four-state model should therefore be regarded as a hypothesis-generating analytical framework rather than a clinicopathological classification system. Future studies should integrate spatially resolved tissue phenotyping, blood and urine biomarkers, and dynamic microcirculatory assessment in longitudinal cohorts. They should test reproducibility, assess prognostic value beyond conventional pathology, estimated glomerular filtration rate, and proteinuria, and determine whether changes in PTC status precede or mediate therapeutic benefit. Linking reproducible microvascular phenotypes to defined mechanisms, treatment response, and long-term renal outcomes will be essential to determine whether state-directed assessment and restoration of the PTC microenvironment can ultimately inform patient stratification and therapeutic decision-making.
2.Integrated molecular characterization of sarcomatoid hepatocellular carcinoma
Rong-Qi SUN ; Yu-Hang YE ; Ye XU ; Bo WANG ; Si-Yuan PAN ; Ning LI ; Long CHEN ; Jing-Yue PAN ; Zhi-Qiang HU ; Jia FAN ; Zheng-Jun ZHOU ; Jian ZHOU ; Cheng-Li SONG ; Shao-Lai ZHOU
Clinical and Molecular Hepatology 2025;31(2):426-444
Background:
s/Aims: Sarcomatoid hepatocellular carcinoma (HCC) is a rare histological subtype of HCC characterized by extremely poor prognosis; however, its molecular characterization has not been elucidated.
Methods:
In this study, we conducted an integrated multiomics study of whole-exome sequencing, RNA-seq, spatial transcriptome, and immunohistochemical analyses of 28 paired sarcomatoid tumor components and conventional HCC components from 10 patients with sarcomatoid HCC, in order to identify frequently altered genes, infer the tumor subclonal architectures, track the genomic evolution, and delineate the transcriptional characteristics of sarcomatoid HCCs.
Results:
Our results showed that the sarcomatoid HCCs had poor prognosis. The sarcomatoid tumor components and the conventional HCC components were derived from common ancestors, mostly accessing similar mutational processes. Clonal phylogenies demonstrated branched tumor evolution during sarcomatoid HCC development and progression. TP53 mutation commonly occurred at tumor initiation, whereas ARID2 mutation often occurred later. Transcriptome analyses revealed the epithelial–mesenchymal transition (EMT) and hypoxic phenotype in sarcomatoid tumor components, which were confirmed by immunohistochemical staining. Moreover, we identified ARID2 mutations in 70% (7/10) of patients with sarcomatoid HCC but only 1–5% of patients with non-sarcomatoid HCC. Biofunctional investigations revealed that inactivating mutation of ARID2 contributes to HCC growth and metastasis and induces EMT in a hypoxic microenvironment.
Conclusions
We offer a comprehensive description of the molecular basis for sarcomatoid HCC, and identify genomic alteration (ARID2 mutation) together with the tumor microenvironment (hypoxic microenvironment), that may contribute to the formation of the sarcomatoid tumor component through EMT, leading to sarcomatoid HCC development and progression.
3.Safety and effectiveness of lecanemab in Chinese patients with early Alzheimer's disease: Evidence from a multidimensional real-world study.
Wenyan KANG ; Chao GAO ; Xiaoyan LI ; Xiaoxue WANG ; Huizhu ZHONG ; Qiao WEI ; Yonghua TANG ; Peijian HUANG ; Ruinan SHEN ; Lingyun CHEN ; Jing ZHANG ; Rong FANG ; Wei WEI ; Fengjuan ZHANG ; Gaiyan ZHOU ; Weihong YUAN ; Xi CHEN ; Zhao YANG ; Ying WU ; Wenli XU ; Shuo ZHU ; Liwen ZHANG ; Naying HE ; Weihuan FANG ; Miao ZHANG ; Yu ZHANG ; Huijun JU ; Yaya BAI ; Jun LIU
Chinese Medical Journal 2025;138(22):2907-2916
INTRODUCTION:
Lecanemab has shown promise in treating early Alzheimer's disease (AD), but its safety and efficacy in Chinese populations remain unexplored. This study aimed to evaluate the safety and 6-month clinical outcomes of lecanemab in Chinese patients with mild cognitive impairment (MCI) or mild AD.
METHODS:
In this single-arm, real-world study, participants with MCI due to AD or mild AD received biweekly intravenous lecanemab (10 mg/kg). The study was conducted at Hainan Branch, Ruijin Hospital Shanghai Jiao Tong University School of Medicine. Patient enrollment and baseline assessments commenced in November 2023. Safety assessments included monitoring for amyloid-related imaging abnormalities (ARIA) and other adverse events. Clinical and biomarker changes from baseline to 6 months were evaluated using cognitive scales (mini-mental state examination [MMSE], montreal cognitive assessment [MoCA], clinical dementia rating-sum of boxes [CDR-SB]), plasma biomarker analysis, and advanced neuroimaging.
RESULTS:
A total of 64 patients were enrolled in this ongoing real-world study. Safety analysis revealed predominantly mild adverse events, with infusion-related reactions (20.3%, 13/64) being the most common. Of these, 69.2% (9/13) occurred during the initial infusion and 84.6% (11/13) did not recur. ARIA-H (microhemorrhages/superficial siderosis) and ARIA-E (edema/effusion) were observed in 9.4% (6/64) and 3.1% (2/64) of participants, respectively, with only two symptomatic cases (one ARIA-E presenting with headache and one ARIA-H with visual disturbances). After 6 months of treatment, cognitive scores remained stable compared to baseline (MMSE: 22.33 ± 5.58 vs . 21.27 ± 4.30, P = 0.733; MoCA: 16.38 ± 6.67 vs . 15.90 ± 4.78, P = 0.785; CDR-SB: 2.30 ± 1.65 vs . 3.16 ± 1.72, P = 0.357), while significantly increasing plasma amyloid-β 42 (Aβ42) (+21.42%) and Aβ40 (+23.53%) levels compared to baseline.
CONCLUSIONS:
Lecanemab demonstrated a favorable safety profile in Chinese patients with early AD. Cognitive stability and biomarker changes over 6 months suggest potential efficacy, though high dropout rates and absence of a control group warrant cautious interpretation. These findings provide preliminary real-world evidence for lecanemab's use in China, supporting further investigation in larger controlled studies.
REGISTRATION
ClinicalTrials.gov , NCT07034222.
Humans
;
Alzheimer Disease/drug therapy*
;
Male
;
Female
;
Aged
;
Middle Aged
;
Cognitive Dysfunction/drug therapy*
;
Aged, 80 and over
;
Amyloid beta-Peptides/metabolism*
;
Biomarkers
;
East Asian People
4.Progress on the mechanism and application of hyperbaric oxygen therapy for neurodegenerative diseases.
Fang-Fang WANG ; Nan WANG ; Heng-Rong YUAN ; Ji XU ; Jun MA ; Xiao-Chen BAO ; Yi-Qun FANG
Acta Physiologica Sinica 2025;77(2):318-326
In 2040, neurodegenerative diseases (NDD) will overtake cancer as the second leading cause of death after cardiovascular and cerebrovascular diseases. Therefore, the search for effective intervention measures has become the top priority to deal with this difficult burden. Hyperbaric oxygen therapy (HBOT) has been used for the past 50 years to treat conditions such as decompression sickness, carbon monoxide poisoning and radiation damage. In recent years, studies have confirmed that HBOT has good effects in improving cognitive impairment after brain injury and stroke, and alleviating neurodegeneration and dysfunction related to NDD. Here we reviewed the pathogenesis and treatment state of NDD, introduced the application of HBOT in animal models and clinical studies of NDD, and expounded the application potential of HBOT in the treatment of NDD from the perspective of mitochondrial function, neuroinflammation, neurogenesis and angiogenesis, oxidative stress, apoptosis, microcirculation and epigenetics.
Hyperbaric Oxygenation
;
Humans
;
Neurodegenerative Diseases/physiopathology*
;
Animals
;
Oxidative Stress
;
Apoptosis
;
Mitochondria/physiology*
;
Neurogenesis
;
Epigenesis, Genetic
5.Comparison of the clinical efficacy in staged open reduction internal fixation and external fixation combined with limited internal fixation for the treatment of high-energy tibial Pilon fracture.
Wei-Qing CHEN ; Ye-Hai CHEN ; Jun-Rong SHU ; Bao-Ping XU ; Bao-Lin CHEN ; Jun-Tao YANG ; Xiu-Po HU
China Journal of Orthopaedics and Traumatology 2025;38(7):716-721
OBJECTIVE:
To compare the clinical efficacy and complication rates of staged open reduction internal fixation (ORIF) and external fixation combined with limited internal fixation (EFLIF) in the treatment of high-energy Pilon fractures.
METHODS:
A retrospective selection was conducted on 78 patients diagnosed with high-energy tibial Pilon fractures who received treatment between January 2021 and October 2023. These patients were categorized into the staged ORIF group and the EFLIF group according to their respective treatment protocols. The staged ORIF group comprised 48 patients, including 29 males and 19 females, aged from 33 to 53 years old with a mean age of (43.25±4.67) years old. The time from injury to treatment averaged (6.54±2.21) hours. All patients received staged ORIF treatment. The EFLIF Group consisted of 30 patients, including 18 males and 12 females, aged from 36 to 54 years old with a mean age of (43.37±3.24) years old. The time from injury to treatment averaged (6.87±1.96) hours. All patients received EFLIF treatment. The recovery of ankle joint function, fracture reduction quality, fracture healing time, and surgical-related indicators between two groups were observed and compared six months after surgery. Additionally, the postoperative complications of the two groups were recorded.
RESULTS:
Both groups of patients were followed up and the duration ranged from 6 to 12 months, with an average of (8.97±1.26) months. At 6-month postoperative follow-up, the American Orthopaedic Foot and Ankle Society (AOFAS) score in the ORIF group was (83.15±20.93), which did not show a statistically significant difference compared to the EFLIF group (81.88±20.67), P>0.05. The excellent and good rate of fracture reduction in the staged ORIF group was 33.33% (16/48), which did not show a statistically significant difference compared to the EFLIF group (30.00%, 9/30), P>0.05. The hospitalization duration and fracture healing time in the staged ORIF group were (16.57±1.25) days and (12.14±1.15) weeks, respectively. When compared to the EFLIF group, which demonstrated a hospitalization duration of (15.97±2.16 ) days and a fracture healing time of (12.36±1.17) weeks, no statistically significant differences were observed (P>0.05). The intraoperative blood loss in the staged ORIF group was (76.54±11.65) ml, which was significantly higher than that in the EFLIF group (70.15±10.29) ml, and the difference was statistically significant (P<0.05). The incidence of superficial tissue infection was 2.08%(1/48), which was significantly lower than that observed in the EFLIF group at 16.67% (5/30), and this difference was statistically significant (P<0.05).
CONCLUSION
Both staged ORIF and EFLIF were effective treatment options for high-energy closed Pilon fractures of the tibia. However, regarding the prevention of superficial tissue infection, staged ORIF demonstrates superior risk control compared to EFLIF.
Humans
;
Male
;
Female
;
Middle Aged
;
Adult
;
Tibial Fractures/physiopathology*
;
Fracture Fixation, Internal/methods*
;
Retrospective Studies
;
External Fixators
;
Open Fracture Reduction/methods*
;
Treatment Outcome
6.Integrated molecular characterization of sarcomatoid hepatocellular carcinoma
Rong-Qi SUN ; Yu-Hang YE ; Ye XU ; Bo WANG ; Si-Yuan PAN ; Ning LI ; Long CHEN ; Jing-Yue PAN ; Zhi-Qiang HU ; Jia FAN ; Zheng-Jun ZHOU ; Jian ZHOU ; Cheng-Li SONG ; Shao-Lai ZHOU
Clinical and Molecular Hepatology 2025;31(2):426-444
Background:
s/Aims: Sarcomatoid hepatocellular carcinoma (HCC) is a rare histological subtype of HCC characterized by extremely poor prognosis; however, its molecular characterization has not been elucidated.
Methods:
In this study, we conducted an integrated multiomics study of whole-exome sequencing, RNA-seq, spatial transcriptome, and immunohistochemical analyses of 28 paired sarcomatoid tumor components and conventional HCC components from 10 patients with sarcomatoid HCC, in order to identify frequently altered genes, infer the tumor subclonal architectures, track the genomic evolution, and delineate the transcriptional characteristics of sarcomatoid HCCs.
Results:
Our results showed that the sarcomatoid HCCs had poor prognosis. The sarcomatoid tumor components and the conventional HCC components were derived from common ancestors, mostly accessing similar mutational processes. Clonal phylogenies demonstrated branched tumor evolution during sarcomatoid HCC development and progression. TP53 mutation commonly occurred at tumor initiation, whereas ARID2 mutation often occurred later. Transcriptome analyses revealed the epithelial–mesenchymal transition (EMT) and hypoxic phenotype in sarcomatoid tumor components, which were confirmed by immunohistochemical staining. Moreover, we identified ARID2 mutations in 70% (7/10) of patients with sarcomatoid HCC but only 1–5% of patients with non-sarcomatoid HCC. Biofunctional investigations revealed that inactivating mutation of ARID2 contributes to HCC growth and metastasis and induces EMT in a hypoxic microenvironment.
Conclusions
We offer a comprehensive description of the molecular basis for sarcomatoid HCC, and identify genomic alteration (ARID2 mutation) together with the tumor microenvironment (hypoxic microenvironment), that may contribute to the formation of the sarcomatoid tumor component through EMT, leading to sarcomatoid HCC development and progression.
7.Quantitative Evaluation of Fingerprint Evidence Value Based on Python
Zhi-Ze XU ; Meng WANG ; Rong-Wei MA ; Jie LI ; Ming LI ; Chuan-Jun YUAN
Chinese Journal of Analytical Chemistry 2025;53(4):590-601,中插12-中插22
A deep learning-based method for recognizing the minutiae in fingerprint,as well as a Python programming-based evaluation system for quantifying the evidence value of fingerprint was proposed.Firstly,latent fingerprints,which were developed using a series of fluorescent nanomaterials synthesized by chemical methods,were used as unknown fingerprint(UKFP),while ink impressed fingerprints were used as known fingerprint(KFP).Then,the bifurcations and terminations in minutiae were recognized using the improved YOLOv8 deep learning model.After that,the similarity index(Sim.)of UKFP vs KFP were calculated by analyzing the angle similarity factor(α)and the curve similarity factor(β)between UKFP and KFP,meanwhile,the sensitivity index(Sen.)were calculated by analyzing the fineness factor(γ)between UKFP and KFP.The evidence value(EV)of fingerprint was thus obtained by the combination of Sim.and Sen..The calculation formulas for above evaluation factors(i.e.α,β and γ),evaluation indexes(i.e.Sim.and Sen.),and EV were also put forward.Finally,the evaluation system for quantifying the evidence value of fingerprint was established,the feasibility and reliability of this system were verified,and the external factors that impacted on Sim.,Sen.,and EV were investigated in detail.The Python-based evaluation system for quantifying the evidence value of fingerprint could achieve the goals objectively,comprehensively,accurately and efficiently,exhibiting easy operability,high efficiency,responsiveness and reliability.This research was expected to provide beneficial references for quantitatively evaluating and thoroughly developing the evidence value.
8.Thoughts and Practices on the Development of Forensic Medicine Discipline in the Perspective of Building a Regional High-Level Medical University
Guang CHEN ; Rong-Shuai WANG ; Li SU ; Yue ZHANG ; Xue-Xia LIU ; Shi-Yong FANG ; Zhan-Zhan LIU ; Ya-Jun XU ; Xiang XU
Journal of Forensic Medicine 2025;41(1):35-39
Under the background of forensic medicine becoming a first-level discipline,the opportuni-ties and challenges of discipline development coexist.Starting from the actual situation and characteris-tics of local medical colleges and universities,this paper discusses the problems and solutions for the development of forensic medicine discipline from the perspective of building a regional high-level medical university.Combined with the experiences of carrying out forensic medicine education in our college,this paper supplies our thoughts and practices on improving the discipline system,enhancing the ability to serve society,perfecting the talent cultivation model and promoting forensic culture,to provide reference and inspiration for the development of forensic medicine in other universities,jointly promote the advancement of forensic medicine in China to a new stage,and contribute the wisdom and strength of forensic medical experts to the construction of a law-based China,a safe China and a healthy China.
9.Integrated molecular characterization of sarcomatoid hepatocellular carcinoma
Rong-Qi SUN ; Yu-Hang YE ; Ye XU ; Bo WANG ; Si-Yuan PAN ; Ning LI ; Long CHEN ; Jing-Yue PAN ; Zhi-Qiang HU ; Jia FAN ; Zheng-Jun ZHOU ; Jian ZHOU ; Cheng-Li SONG ; Shao-Lai ZHOU
Clinical and Molecular Hepatology 2025;31(2):426-444
Background:
s/Aims: Sarcomatoid hepatocellular carcinoma (HCC) is a rare histological subtype of HCC characterized by extremely poor prognosis; however, its molecular characterization has not been elucidated.
Methods:
In this study, we conducted an integrated multiomics study of whole-exome sequencing, RNA-seq, spatial transcriptome, and immunohistochemical analyses of 28 paired sarcomatoid tumor components and conventional HCC components from 10 patients with sarcomatoid HCC, in order to identify frequently altered genes, infer the tumor subclonal architectures, track the genomic evolution, and delineate the transcriptional characteristics of sarcomatoid HCCs.
Results:
Our results showed that the sarcomatoid HCCs had poor prognosis. The sarcomatoid tumor components and the conventional HCC components were derived from common ancestors, mostly accessing similar mutational processes. Clonal phylogenies demonstrated branched tumor evolution during sarcomatoid HCC development and progression. TP53 mutation commonly occurred at tumor initiation, whereas ARID2 mutation often occurred later. Transcriptome analyses revealed the epithelial–mesenchymal transition (EMT) and hypoxic phenotype in sarcomatoid tumor components, which were confirmed by immunohistochemical staining. Moreover, we identified ARID2 mutations in 70% (7/10) of patients with sarcomatoid HCC but only 1–5% of patients with non-sarcomatoid HCC. Biofunctional investigations revealed that inactivating mutation of ARID2 contributes to HCC growth and metastasis and induces EMT in a hypoxic microenvironment.
Conclusions
We offer a comprehensive description of the molecular basis for sarcomatoid HCC, and identify genomic alteration (ARID2 mutation) together with the tumor microenvironment (hypoxic microenvironment), that may contribute to the formation of the sarcomatoid tumor component through EMT, leading to sarcomatoid HCC development and progression.
10.Body fat distribution and semen quality in 4304 Chinese sperm donors.
Si-Han LIANG ; Qi-Ling WANG ; Dan LI ; Gui-Fang YE ; Ying-Xin LI ; Wei ZHOU ; Rui-Jun XU ; Xin-Yi DENG ; Lu LUO ; Si-Rong WANG ; Xin-Zong ZHANG ; Yue-Wei LIU
Asian Journal of Andrology 2025;27(4):524-530
Extensive studies have identified potential adverse effects on semen quality of obesity, based on body mass index, but the association between body fat distribution, a more relevant indicator for obesity, and semen quality remains less clear. We conducted a longitudinal study of 4304 sperm donors from the Guangdong Provincial Human Sperm Bank (Guangzhou, China) during 2017-2021. A body composition analyzer was used to measure total and local body fat percentage for each participant. Generalized estimating equations were employed to assess the association between body fat percentage and sperm count, motility, and morphology. We estimated that each 10% increase in total body fat percentage (estimated change [95% confidence interval, 95% CI]) was significantly associated with a 0.18 × 10 6 (0.09 × 10 6 -0.27 × 10 6 ) ml and 12.21 × 10 6 (4.52 × 10 6 -19.91 × 10 6 ) reduction in semen volume and total sperm count, respectively. Categorical analyses and exposure-response curves showed that the association of body fat distribution with semen volume and total sperm count was stronger at higher body fat percentages. In addition, the association still held among normal weight and overweight participants. We observed similar associations for upper limb, trunk, and lower limb body fact distributions. In conclusion, we found that a higher body fat distribution was significantly associated with lower semen quality (especially semen volume) even in men with a normal weight. These findings provide useful clues in exploring body fat as a risk factor for semen quality decline and add to evidence for improving semen quality for those who are expected to conceive.
Humans
;
Male
;
Adult
;
Semen Analysis
;
China
;
Body Fat Distribution
;
Longitudinal Studies
;
Sperm Count
;
Sperm Motility
;
Body Mass Index
;
Tissue Donors
;
Obesity/complications*
;
Spermatozoa
;
Young Adult
;
Middle Aged
;
East Asian People

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