1.Research on the correlation between Ddit3-Trib3-Akt signaling pathway and spermatogenesis in rats based on the testicular tissue co-culture system
Yan LI ; Shanshan LIU ; Lin GAO ; Lingyi KONG ; Xia YUN ; Yan ZHANG ; Taodi LIU
Acta Universitatis Medicinalis Anhui 2026;61(1):91-97
ObjectiveTo verify the association between the Ddit3-Trib3-Akt signaling pathway and rat spermatogenesis by constructing an in vitro co-culture system of testis. MethodsTesticular tissue blocks from 20-25-day-old male rats were placed in an in vitro culture system, and the culture medium was replaced every 2 to 3 days. PCR was used to verify the expression of marker genes of various spermatogenic cells. RNA interference technology was employed to verify the correlation between the Ddit3-Trib3-Akt signaling pathway and rat spermatogenesis. ResultsThe co-culture system could be continuously cultured for more than 2.5 months in vitro. RT-PCR showed that specific marker genes of spermatogonia, spermatocyte and spermoblast were expressed. The RNA and protein expression of Trib3 and Akt changed after the knocking down of Ddit3 and Trib3, respectively. It demonstrated the existence of Ddit3-Trib3-Akt signaling pathway in rat spermatogenesis. ConclusionThe culture time of more than 2.5 months indicates that the culture system can temporarily maintain the proliferation and differentiation of stem cells, and simultaneously maintain and stabilize spermatogenesis in a simple system. The successful validation of the Ddit3-Trib3-Akt signaling pathway also confirms that this culture system can be used to study possible molecular mechanisms of spermatogenesis in vitro.
2.The causal relationship between immune cells and heart failure risk and the mediating role of serum metabolites: A Mendelian randomization study
Yun ZHU ; Jiaming WEI ; Ruifang LIN ; Yongjun LIU ; Yue LIU ; Guohua ZHANG ; Zhihua GUO
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(01):115-121
Objective To explore the causal relationship between immune cells and heart failure (HF), and the mediating role of serum metabolites, in order to identify potential biomarkers and therapeutic targets. Methods We employed a two-sample Mendelian randomization (MR) analysis method based on genome-wide association study (GWAS) data, analyzing the direct and indirect effects of 731 types of immune cells and 1 400 metabolites on HF. We selected valid instrumental variables and conducted statistical analyses using R software. The primary analysis was performed using the inverse variance weighted method, supplemented by MR-Egger analysis and weighted median method. The stability of the results was assessed through tests such as Cochran’s Q test. Results Our research found a negative causal relationship between PD-L1 on CD14−CD16+ and HF. Sensitivity analysis supported this result. The reverse MR analysis did not find an effect of HF on PD-L1 on CD14−CD16+, indicating that PD-L1 on CD14−CD16+ might play a unidirectional role in reducing the risk of HF. Further mediation MR analysis showed that PD-L1 on CD14−CD16+ might influence the risk of HF onset by regulating the levels of sphingomyelin (d17:1/14:0, d16:1/15:0), with a mediation effect ratio of 6.7%. Conclusion PD-L1 on CD14−CD16+ may reduce the risk of HF by elevating the levels of sphingomyelin (d17:1/14:0, d16:1/15:0), which provides a new perspective for understanding the pathogenesis of HF.
3.Research hotspots and visual analysis on the medical artificial intelligence ethics at home and abroad
Mengze LYU ; Hongji LIN ; Ya’nan BA ; Yan ZHANG ; Jin XIE ; Yun LIU
Chinese Medical Ethics 2026;39(3):287-299
To conduct a bibliometric and keyword analysis on the domestic and international literature of medical artificial intelligence (AI) ethics, explore the research frontiers, hotspots, and development trends in this field, and provide references for promoting the construction of China’s ethical governance system on medical AI. Utilizing CiteSpace software, a comparative analysis was conducted between the reviewed domestic and international literature regarding their publication volume, author and institutional collaboration networks, as well as keyword co-occurrence, clustering, timeline graph, and burst, to explore the research hotspots and development trends in the field. A total of 2 393 Chinese and English publications were included. In recent years, research topics in medical AI ethics both domestically and internationally focused on three aspects, encompassing their theoretical research, emerging domains and their ethical risks, as well as the ethical governance and regulation of medical AI. International research hotspots included federated learning, computer-aided detection, informed consent, and other aspects, whereas domestic research hotspots were smart healthcare, responsibility ethics, ethical values, and other aspects. Internationally, greater attention was placed on ethical issues concerning population health and healthcare in the public health domain, whereas domestic research topics tended to focus more on theoretical discussions and the establishment of ethical principles. The ethical governance of medical AI represents a shared global challenge, necessitating enhanced research into both the variances and commonalities in this field.
4.Fluorescence Suppression Method of Raman Spectroscopy and Its Application in Skin and Cosmetics Analysis
Yun-Xia CHEN ; Jia-Rong WANG ; Jian-Yu ZHU ; Shi-Wen LIN ; Ya-Nan LIU ; Xiao-Yue MA ; Guang-Cheng XI ; Juan LIU
Progress in Biochemistry and Biophysics 2026;53(7):1914-1926
Owing to its inherent advantages—such as being non-destructive, rapid, highly molecule-specific, and minimally interfered with by moisture—Raman spectroscopy has been widely adopted in the fields of skin barrier function assessment, monitoring the transdermal penetration of active cosmetic ingredients, and the identification and quality control of cosmetic products. Despite these strengths, the practical application of this technique faces a significant bottleneck: the strong fluorescence background generated by endogenous skin components and exogenous cosmetic additives. Endogenous skin substances, such as structural proteins (e.g., collagen and elastin), metabolic coenzymes (e.g., nicotinamide adenine dinucleotide), and pigments (e.g., melanin), together with exogenous cosmetic constituents like organic colorants, chemical sunscreens, and fragrances, often possess strong absorption and emission characteristics. When excited by lasers, these components produce a fluorescence background that can be 106 to 108 times stronger than the Raman scattering signals, effectively masking the inherently weak vibrational fingerprint information. In recent years, driven by the rapid development of optoelectronic hardware and artificial intelligence algorithms, fluorescence suppression strategies have evolved from isolated, single-method approaches into comprehensive, multi-level synergistic systems. These systems are categorized into three distinct tiers: sample preparation, signal acquisition, and data processing. At the sample preparation level, techniques such as photobleaching and surface-enhanced Raman spectroscopy (SERS) are employed to eliminate or bypass the generation of fluorescence at the source. At the signal acquisition level, instrumental improvements—including the use of long-wavelength near-infrared excitation (typically 785 nm or 1 064 nm), confocal spatial filtering, and shifted excitation Raman difference spectroscopy (SERDS)— are utilized to physically isolate Raman signals from the fluorescence background. Furthermore, at the data processing level, numerical baseline correction methods such as polynomial fitting, penalized least squares (e.g., airPLS, arPLS), wavelet transform, and derivative algorithms are increasingly integrated into the analytical pipeline to extract Raman spectral features from mixed signals without increasing hardware costs or acquisition time. This review provides a systematic categorization and critical evaluation of these fluorescence suppression methods, detailing their underlying principles, technical advantages, and inherent limitations in diverse experimental setups. By focusing on critical application scenarios—including skin barrier assessment, percutaneous absorption monitoring, the routine quality control of cosmetics, and the emerging field of portable on-site detection—this paper explores the current state of technique selection and optimization. Finally, the article discusses future development trends, emphasizing the necessity of constructing adaptive, tiered suppression strategies, developing intelligent and automated data processing algorithms, and promoting the integration of portable, multi-modal diagnostic devices. The objective of this review is to provide a comprehensive technical reference to facilitate the transition of Raman spectroscopy from a specialized laboratory tool into a routine, robust analytical platform for advancements in skin science and cosmetic research.
5.Analysis of Volatile Component Variations in Coptidis Rhizoma Processed with Euodiae Fructus Juice by HS-SPME-GC-MS Combined with Chemometrics and ROAV
Lin YAN ; Yun WANG ; Puling LI ; Lingbang MENG ; Zhe JIA ; Ying LI ; Ying LIU ; Min JIN ; Cun ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(21):218-225
ObjectiveTo analyze the volatile components in raw Coptidis Rhizoma, Euodiae Fructus juice-processed Coptidis Rhizoma (Yuhuanglian), and the processing adjuvant Euodiae Fructus juice, identify marker volatile components in the processed product, and elucidate the material basis changes during the processing with Euodiae Fructus juice. MethodsHeadspace solid-phase microextraction coupled with gas chromatography-quadrupole-time-of-flight mass spectrometry (HS-SPME-GC-Q-TOF-MS) was employed to analyze the volatile components in raw Coptidis Rhizoma, Yuhuanglian, and Euodiae Fructus juice. Chemometric analysis was performed to compare volatile components among samples and screen the marker components. Finally, the relative odor activity value (ROAV) was calculated to investigate odor characteristics. ResultsA total of 127 components were detected, with 27, 75, 84 volatile components identified in Euodiae Fructus juice, raw Coptidis Rhizoma, and Yuhuanglian, respectively. Processing with Euodiae Fructus juice significantly increased the number and content of volatile components. Chemometric analysis revealed significant changes in volatile components among the three sample types, allowing clear discrimination. After processing, 39 components such as methyl octanoate and allyl propionate were introduced, while 34 components including furfural and hexanoic acid increased in content, and 11 components including butyric acid and octanal decreased. Additionally, eight components, including zingiberene, 6-methyl-6-hepten-2-one, and 5-methyl-2-hexanone, were screened as marker components of Yuhuanglian. Moreover, processing enhanced the ROAV values of 2,5-dimethylpyrazine (roasted, nutty, coffee-like aroma), 3-ethylphenol, and guaiacol (smoky, woody aroma). Additionally, it incorporated 1-hepten-3-one from Euodiae Fructus juice and the newly generated 1-hexen-3-one, contributing mushroom and cucumber-like odors. The sensory profile of Yuhuanglian integrated nutty, roasted, smoky, and woody notes with the citrus and fruity aroma originally contributed by octanal. ConclusionThe processing with Euodiae Fructus juice introduced components from adjuvant, significantly altering the volatile component profile and enhancing the sensory odor characteristics of Yuhuanglian. This study provides a valuable reference for exploring the material basis of volatile components and establishing processing specifications for Yuhuanglian.
6.Analysis of Volatile Component Variations in Coptidis Rhizoma Processed with Euodiae Fructus Juice by HS-SPME-GC-MS Combined with Chemometrics and ROAV
Lin YAN ; Yun WANG ; Puling LI ; Lingbang MENG ; Zhe JIA ; Ying LI ; Ying LIU ; Min JIN ; Cun ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(21):218-225
ObjectiveTo analyze the volatile components in raw Coptidis Rhizoma, Euodiae Fructus juice-processed Coptidis Rhizoma (Yuhuanglian), and the processing adjuvant Euodiae Fructus juice, identify marker volatile components in the processed product, and elucidate the material basis changes during the processing with Euodiae Fructus juice. MethodsHeadspace solid-phase microextraction coupled with gas chromatography-quadrupole-time-of-flight mass spectrometry (HS-SPME-GC-Q-TOF-MS) was employed to analyze the volatile components in raw Coptidis Rhizoma, Yuhuanglian, and Euodiae Fructus juice. Chemometric analysis was performed to compare volatile components among samples and screen the marker components. Finally, the relative odor activity value (ROAV) was calculated to investigate odor characteristics. ResultsA total of 127 components were detected, with 27, 75, 84 volatile components identified in Euodiae Fructus juice, raw Coptidis Rhizoma, and Yuhuanglian, respectively. Processing with Euodiae Fructus juice significantly increased the number and content of volatile components. Chemometric analysis revealed significant changes in volatile components among the three sample types, allowing clear discrimination. After processing, 39 components such as methyl octanoate and allyl propionate were introduced, while 34 components including furfural and hexanoic acid increased in content, and 11 components including butyric acid and octanal decreased. Additionally, eight components, including zingiberene, 6-methyl-6-hepten-2-one, and 5-methyl-2-hexanone, were screened as marker components of Yuhuanglian. Moreover, processing enhanced the ROAV values of 2,5-dimethylpyrazine (roasted, nutty, coffee-like aroma), 3-ethylphenol, and guaiacol (smoky, woody aroma). Additionally, it incorporated 1-hepten-3-one from Euodiae Fructus juice and the newly generated 1-hexen-3-one, contributing mushroom and cucumber-like odors. The sensory profile of Yuhuanglian integrated nutty, roasted, smoky, and woody notes with the citrus and fruity aroma originally contributed by octanal. ConclusionThe processing with Euodiae Fructus juice introduced components from adjuvant, significantly altering the volatile component profile and enhancing the sensory odor characteristics of Yuhuanglian. This study provides a valuable reference for exploring the material basis of volatile components and establishing processing specifications for Yuhuanglian.
7.Brain-heart Axis in Neurodegenerative and Cardiovascular Comorbidity: Oxidative Stress, Inflammation, and Biomarkers
Xu-Lin LIU ; Ying-Ao XIE ; Yun-Fei WANG ; Jing CHENG ; Qiao-Qiao LI
Progress in Biochemistry and Biophysics 2026;53(10):2558-2582
Neurodegenerative diseases (NDs), particularly Alzheimer’s disease (AD) and Parkinson’s disease (PD), and cardiovascular diseases (CVDs), including heart failure (HF) and coronary artery disease (CAD), are major chronic disorders associated with population aging. Their frequent coexistence in clinical practice suggests that they may not progress independently, but may instead be linked through bidirectional pathological communication within the brain-heart axis. Epidemiological evidence underscores this clinical burden: systematic reviews and meta-analyses have reported pooled relative risks for dementia of approximately 1.27 among individuals with a history of CAD and 1.60 among those with HF, while the pooled prevalence of cognitive impairment and dementia in patients with HF has been estimated at approximately 41.42% and 19.79%, respectively. This review synthesizes current evidence on the mechanistic links, disease-state manifestations, biomarkers, and potential therapeutic strategies involved in the comorbidity between NDs and CVDs from the perspective of the brain-heart axis. The brain and heart communicate through autonomic, neuroendocrine, neuroimmune, vascular, and humoral pathways. Sympathetic activation, parasympathetic withdrawal, vagal dysfunction, cerebral hypoperfusion, endothelial injury, blood-brain barrier (BBB) alterations, peripheral immune activation, and circulating inflammatory mediators may jointly contribute to cross-organ pathological signaling. Oxidative stress and inflammatory response are not specific to the brain-heart axis; rather, they may act as candidate amplifying processes within this network. Mitochondrial dysfunction and NADPH oxidase activation can increase the generation of reactive oxygen species and reactive nitrogen species, which may activate nuclear factor-κB, the NLRP3 inflammasome, and mitogen-activated protein kinase/c-Jun N-terminal kinase signaling. These pathways can promote the release of interleukin-1β, interleukin-6, tumor necrosis factor‑α, and other inflammatory mediators, which may in turn aggravate mitochondrial injury, endothelial dysfunction, immune cell activation, and further oxidant generation. Cytokines, chemokines, oxidized lipids, mitochondrial DNA, damage-associated molecular patterns, and extracellular vesicles may transmit these signals between the cardiovascular and central nervous systems, whereas autonomic reflexes provide an additional route for bidirectional amplification. Distinct disease states illustrate different manifestations of this network. The association between AD and CVDs may involve vascular risk factors, impaired amyloid-β clearance, abnormal cholesterol homeostasis, cerebral microvascular injury, neuroinflammation, and endothelial dysfunction. HF-related cognitive impairment may be linked to reduced cardiac output, recurrent cerebral hypoperfusion, hypoxia-related signaling, BBB dysfunction, circulating inflammation, and impaired autonomic feedback. In PD, cardiovascular autonomic dysfunction and abnormalities in heart rate and blood pressure regulation may interact with vascular injury, reduced cerebral perfusion, inflammation, and oxidative stress. However, the relationship between PD and CAD remains heterogeneous and may be modified by age, ethnicity, medication use, metabolic factors, and coexisting diseases. Biomarker evaluation should therefore move beyond isolated indicators. Traditional markers, including malondialdehyde, superoxide dismutase, glutathione, C-reactive protein, and interleukin-6, reflect systemic oxidative or inflammatory burden but lack sufficient specificity to distinguish primary neurodegeneration, cardiovascular injury, or a comorbid state involving both. Greater clinical value may be obtained from cross-system panels that combine oxidative stress and inflammatory markers with cardiac stress or injury biomarkers, such as N-terminal pro-B-type natriuretic peptide; glial or neuronal biomarkers, such as glial fibrillary acidic protein and neurofilament light chain; BBB- or endothelial injury-related biomarkers; and omics-derived candidates, including microRNAs, long non-coding RNAs, DNA methylation signatures, metabolites, and proteins. Multi-omics integration and artificial intelligence-assisted analysis may support risk stratification, disease monitoring, and prediction of treatment response. However, these approaches require standardized analytical platforms, validation in independent cohorts, and careful distinction between associative findings and causal mechanisms. Potential interventions include antioxidant, anti-inflammatory, mitochondria-targeted, and multi-target combination strategies, together with emerging approaches such as nanodelivery, CRISPR/Cas9- or CRISPR/dCas9-based regulation, mesenchymal stem cell-mediated mitochondrial transfer, and ergothioneine supplementation. Nevertheless, most available evidence is indirect, preclinical, or derived from other disease indications, and no single drug or technology can currently be regarded as specific to brain-heart axis comorbidity. The clinical relevance of these strategies will depend on whether they can be matched to dominant pathological phenotypes and improve both neurological and cardiovascular outcomes. Overall, comorbidity between NDs and CVDs is more appropriately understood as a heterogeneous cross-organ regulatory network than as a disorder driven by a single pathway. Future research should prioritize multicenter longitudinal cohorts, standardized clinical phenotyping, validation of cross-system biomarker panels, and mechanism-guided interventions in clearly defined patient subgroups, with integrated assessment of cognitive function, cardiovascular events, quality of life, long-term safety, and treatment response.
8.Survey and drug resistance analysis on pathogens in the intestines of healthy humans in Guangzhou from 2018 to 2023
Shuang MA ; Yun XIAO ; Bixia KE ; Fangzhu OUYANG ; Keng LIN ; Yanxia LIU ; Xiang MA ; Bosheng LI ; Dongmei HE
International Journal of Laboratory Medicine 2025;46(10):1221-1226,1233
Objective To investigate the carrying status and drug resistance analysis of pathogenic bacteria in the gut of healthy population in Huadu District,Guangzhou,and provide reference for epidemiological re-search.Methods A total of 337 459 anal swabs were directly isolated and cultured from healthy individuals who underwent physical examinations from 2018 to 2023.600 anal swabs from 2022 were randomly selected for multi pathogen nucleic acid testing,direct isolation and culture,and enrichment culture.Identification of bacteria was conducted by using VITEK 2 Compact and VITEK MS,serological testing was used for determi-nation of type,and drug susceptibility testing of pathogenic bacteria was conducted.Results A total of 128 pathogenic bacteria were isolated from rectal swabs,including 52 strains of Salmonella,71 strains of Aero-monas,3 strains of Vibrio parahaemolyticus,and 2 strains of Shigella flexneri,with a total detection rate of 3.79/10 000.The detection rate of Salmonella in direct isolation and culture of 600 rectal swabs was 0.50%,the detection rate of enrichment culture was 1.00%,and the detection rate of multi-pathogen nucleic acid de-tection was 1.17%.52 strains of Salmonella were divided into 27 serotypes,and Salmonella Ⅰ 4,5,12:i:—was the dominant serotype.Aeromonas sobria was the dominant serotype in Aeromonas.The sensitivity of Salmonella to piperacillin/tazobactam,imipenem,cefepime,levofloxacin,and aztreonam was up to 92.00%or more,however,the phenomenon of multidrug resistance was severe,with a multidrug resistance rate as high as 40.38%.The resistance rate of Aeromonas to ampicillin and ampicillin/sulbactam was up to 85.00%or more,while Aeromonas was relatively sensitive to other antibiotics.Conclusion There are many species and types of intestinal pathogenic bacteria carried by healthy individuals in Huadu District,Guangzhou,with Aero-monas and Salmonella ranking first and second,and levofloxacin treatment could be preferred.The use of bac-terial culture and multi pathogen nucleic acid testing methods could improve the detection rate of intestinal pathogenic bacteria,and attention should be paid to the monitoring of intestinal pathogenic bacteria among rel-evant practitioners.
9.Tubeless subxiphoid uniportal video-assisted thoracoscopic surgery with percutaneous suspension technique via balance-shaped sternal elevation device in anterior mediastinal masses
Junmin ZHU ; Junjie WANG ; Jianming YUE ; Yixin SUN ; Yichen LIU ; Lei WANG ; Lin LIN ; Jie LI ; Jinlan ZHAO ; Xuehua TU ; Ningying DING ; Jianrong HU ; Chunmei HE ; Leilei TIAN ; Hongtao TANG ; Jiasheng ZHAO ; Cheng CHEN ; Yongxiang SONG ; Yunwei TIAN ; Yong XIAO ; Kaidi LI ; Lin MA ; Yun WANG ; Longqi CHEN ; Dong TIAN
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2025;32(11):1603-1609
Objective To assess the clinical value of a novel surgical technique—Tubeless subxiphoid uniportal video-assisted thoracoscopic surgery with percutaneous suspension technique via balance-shaped sternal elevation device in the resection of anterior mediastinal masses. Methods Patients who underwent tubeless subxiphoid uniportal video-assisted thoracoscopic surgery via balance-shaped sternal elevation device in anterior mediastinal masses process at the Department of Thoracic Surgery, West China Hospital, Sichuan University from March to April 2025 were included, and their clinical data were analyzed. Results A total of 4 patients were included, with 2 males and 2 females, aged 58-75 years. The diameter of the tumor was 2.5-3.0 cm. The operation time was 60.0-150.0 min, intraoperative blood loss was 5-10 mL, pain score on the 3rd day after surgery was 0 points, and postoperative hospital stay was 2-3 days. All patients achieved complete resection of the masses and thymus without perioperative complications. Conclusion The tubeless subxiphoid uniportal video-assisted thoracoscopic surgery with percutaneous suspension technique via balance-shaped sternal elevation device technique optimizes surgical visualization and instrument maneuverability while avoiding complications related to conventional anesthesia and tubing, thereby markedly enhancing the minimally invasive profile of anterior mediastinal masses resections. In addition to maintaining procedural safety, this approach effectively reduces postoperative pain and accelerates patient recovery, highlighting its potential for widespread clinical adoption.
10.Coral calcium hydride promotes peripheral mitochondrial division and reduces AT-Ⅱ cells damage in ARDS via activation of the Trx2/Myo19/Drp1 pathway
Qian LI ; Yang ANG ; Qing-Qing ZHOU ; Min SHI ; Wei CHEN ; Yujie WANG ; Pan YU ; Bing WAN ; Wanyou YU ; Liping JIANG ; Yadan SHI ; Zhao LIN ; Shaozheng SONG ; Manlin DUAN ; Yun LONG ; Qi WANG ; Wentao LIU ; Hongguang BAO
Journal of Pharmaceutical Analysis 2025;15(3):610-624
Acute respiratory distress syndrome(ARDS)is a common respiratory emergency,but current clinical treatment remains at the level of symptomatic support and there is a lack of effective targeted treatment measures.Our previous study confirmed that inhalation of hydrogen gas can reduce the acute lung injury of ARDS,but the application of hydrogen has flammable and explosive safety concerns.Drinking hydrogen-rich liquid or inhaling hydrogen gas has been shown to play an important role in scavenging reactive oxygen species and maintaining mitochondrial quality control balance,thus improving ARDS in patients and animal models.Coral calcium hydrogenation(CCH)is a new solid molecular hydrogen carrier prepared from coral calcium(CC).Whether and how CCH affects acute lung injury in ARDS re-mains unstudied.In this study,we observed the therapeutic effect of CCH on lipopolysaccharide(LPS)induced acute lung injury in ARDS mice.The survival rate of mice treated with CCH and hydrogen inhalation was found to be comparable,demonstrating a significant improvement compared to the untreated ARDS model group.CCH treatment significantly reduced pulmonary hemorrhage and edema,and improved pulmonary function and local microcirculation in ARDS mice.CCH promoted mitochon-drial peripheral division in the early course of ARDS by activating mitochondrial thioredoxin 2(Trx2),improved lung mitochondrial dysfunction induced by LPS,and reduced oxidative stress damage.The results indicate that CCH is a highly efficient hydrogen-rich agent that can attenuate acute lung injury of ARDS by improving the mitochondrial function through Trx2 activation.

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