1.Noninvasive Screening for Chronic Atrophic Gastritis Using Photoplethysmography-derived Meridian-labelled Harmonic Parameters
Yun-Qing LE ; Jian-Xin CHEN ; Ai-Ping CHEN ; Zhi-Hong LI
Progress in Biochemistry and Biophysics 2026;53(5):1178-1194
ObjectiveChronic atrophic gastritis (CAG) is usually diagnosed by gastroscopy and histopathological biopsy. These procedures remain the reference standard, but their invasive nature and resource requirements may limit their use in large-scale population screening and repeated follow-up. A convenient and reproducible method for noninvasive auxiliary screening may help identify individuals who require further endoscopic assessment. Fingertip photoplethysmography (PPG) provides a noninvasive recording of peripheral pulse waves and allows harmonic features to be extracted from the signal. In this study, the so-called meridian-related variables were defined as PPG-derived harmonic parameters labelled according to meridian nomenclature, rather than as direct measurements of meridian physiology. This study aimed to compare these harmonic parameters between patients with CAG and non-CAG controls, identify parameters that remained different after age adjustment, and develop a multivariable model for noninvasive auxiliary screening and pre-endoscopic risk stratification of CAG. MethodsA total of 343 participants were included, comprising 171 patients with CAG and 172 non-CAG controls. CAG diagnosis was established using gastroscopy and histopathology as the reference standard. Fingertip PPG signals were collected using a PPG-based pulse acquisition device. Eight PPG-derived harmonic parameters labelled according to meridian nomenclature were extracted for analysis. Between-group differences were first assessed using nonparametric tests. Age-adjusted analyses were then performed to reduce potential confounding by age. The false discovery rate (FDR) method was applied for multiple-comparison correction. A multivariable logistic regression model integrating age and multiple harmonic parameters was constructed. Model performance was evaluated using receiver operating characteristic (ROC) analysis and the area under the curve (AUC). Internal validation performance was assessed using stratified five-fold cross-validation and bootstrap optimism correction. Threshold performance was examined using both a high-specificity strategy and a Youden index-based cutoff. Decision curve analysis was used to evaluate the model’s net clinical benefit across a range of threshold probabilities. ResultsAll eight harmonic parameters were non-normally distributed. In the univariate analysis, the stomach-labelled harmonic parameter (ST), bladder-labelled harmonic parameter (BL), and liver-labelled harmonic parameter (LR) differed between the CAG and non-CAG groups. After age adjustment and FDR correction, only ST and BL remained statistically significant. Compared with non-CAG controls, patients with CAG showed higher ST values and lower BL values. This finding indicates an associated differential harmonic pattern that was not fully explained by age distribution. However, the discriminative ability of a single harmonic parameter was limited. The best-performing single indicator was ST, with an AUC of 0.652 (95% CI: 0.595-0.707). The multivariable model integrating age and multiple harmonic parameters achieved an AUC of 0.791 (95% CI: 0.743-0.835), representing an improvement of 0.139 over ST alone. In internal validation, stratified five-fold cross-validation yielded a mean AUC of 0.753 (95% CI: 0.715-0.781), and the bootstrap optimism-corrected AUC was 0.748. These results suggest that the model retained moderate discriminative performance after internal validation.At a specificity of at least 95%, the model achieved a sensitivity of only 40.4% (95% CI: 25.7%-49.7%). This high-specificity cutoff may be suboptimal as the preferred threshold for an initial screening setting because of the potential risk of missed CAG cases. The Youden index-based optimal cutoff was 0.419, corresponding to a sensitivity of 80.7% and a specificity of 62.8%. This threshold may better match the practical aim of noninvasive auxiliary screening, where sensitivity is usually prioritized to reduce missed cases. Decision curve analysis showed that, within a threshold probability range of 10%-55%, the model provided higher net clinical benefit than the reference strategies of recommending gastroscopy for all participants or for none. ConclusionPatients with CAG showed associated harmonic differences in fingertip PPG-derived features, mainly characterized by higher ST and lower BL values after age adjustment and FDR correction. Compared with a single harmonic parameter, the multivariable model showed better overall discrimination and retained moderate internal validation performance. These findings suggest that PPG-derived harmonic parameters labelled according to meridian nomenclature may provide auxiliary information for noninvasive auxiliary screening and front-line triage before gastroscopic confirmation in CAG. The present results support further validation rather than immediate clinical implementation. External validation in independent, multicenter, and preferably prospective screening cohorts is needed to assess the model’s generalizability, screening performance, and potential clinical utility.
2.Noninvasive Screening for Chronic Atrophic Gastritis Using Photoplethysmography-derived Meridian-labelled Harmonic Parameters
Yun-Qing LE ; Jian-Xin CHEN ; Ai-Ping CHEN ; Zhi-Hong LI
Progress in Biochemistry and Biophysics 2026;53(5):1178-1194
ObjectiveChronic atrophic gastritis (CAG) is usually diagnosed by gastroscopy and histopathological biopsy. These procedures remain the reference standard, but their invasive nature and resource requirements may limit their use in large-scale population screening and repeated follow-up. A convenient and reproducible method for noninvasive auxiliary screening may help identify individuals who require further endoscopic assessment. Fingertip photoplethysmography (PPG) provides a noninvasive recording of peripheral pulse waves and allows harmonic features to be extracted from the signal. In this study, the so-called meridian-related variables were defined as PPG-derived harmonic parameters labelled according to meridian nomenclature, rather than as direct measurements of meridian physiology. This study aimed to compare these harmonic parameters between patients with CAG and non-CAG controls, identify parameters that remained different after age adjustment, and develop a multivariable model for noninvasive auxiliary screening and pre-endoscopic risk stratification of CAG. MethodsA total of 343 participants were included, comprising 171 patients with CAG and 172 non-CAG controls. CAG diagnosis was established using gastroscopy and histopathology as the reference standard. Fingertip PPG signals were collected using a PPG-based pulse acquisition device. Eight PPG-derived harmonic parameters labelled according to meridian nomenclature were extracted for analysis. Between-group differences were first assessed using nonparametric tests. Age-adjusted analyses were then performed to reduce potential confounding by age. The false discovery rate (FDR) method was applied for multiple-comparison correction. A multivariable logistic regression model integrating age and multiple harmonic parameters was constructed. Model performance was evaluated using receiver operating characteristic (ROC) analysis and the area under the curve (AUC). Internal validation performance was assessed using stratified five-fold cross-validation and bootstrap optimism correction. Threshold performance was examined using both a high-specificity strategy and a Youden index-based cutoff. Decision curve analysis was used to evaluate the model’s net clinical benefit across a range of threshold probabilities. ResultsAll eight harmonic parameters were non-normally distributed. In the univariate analysis, the stomach-labelled harmonic parameter (ST), bladder-labelled harmonic parameter (BL), and liver-labelled harmonic parameter (LR) differed between the CAG and non-CAG groups. After age adjustment and FDR correction, only ST and BL remained statistically significant. Compared with non-CAG controls, patients with CAG showed higher ST values and lower BL values. This finding indicates an associated differential harmonic pattern that was not fully explained by age distribution. However, the discriminative ability of a single harmonic parameter was limited. The best-performing single indicator was ST, with an AUC of 0.652 (95% CI: 0.595-0.707). The multivariable model integrating age and multiple harmonic parameters achieved an AUC of 0.791 (95% CI: 0.743-0.835), representing an improvement of 0.139 over ST alone. In internal validation, stratified five-fold cross-validation yielded a mean AUC of 0.753 (95% CI: 0.715-0.781), and the bootstrap optimism-corrected AUC was 0.748. These results suggest that the model retained moderate discriminative performance after internal validation.At a specificity of at least 95%, the model achieved a sensitivity of only 40.4% (95% CI: 25.7%-49.7%). This high-specificity cutoff may be suboptimal as the preferred threshold for an initial screening setting because of the potential risk of missed CAG cases. The Youden index-based optimal cutoff was 0.419, corresponding to a sensitivity of 80.7% and a specificity of 62.8%. This threshold may better match the practical aim of noninvasive auxiliary screening, where sensitivity is usually prioritized to reduce missed cases. Decision curve analysis showed that, within a threshold probability range of 10%-55%, the model provided higher net clinical benefit than the reference strategies of recommending gastroscopy for all participants or for none. ConclusionPatients with CAG showed associated harmonic differences in fingertip PPG-derived features, mainly characterized by higher ST and lower BL values after age adjustment and FDR correction. Compared with a single harmonic parameter, the multivariable model showed better overall discrimination and retained moderate internal validation performance. These findings suggest that PPG-derived harmonic parameters labelled according to meridian nomenclature may provide auxiliary information for noninvasive auxiliary screening and front-line triage before gastroscopic confirmation in CAG. The present results support further validation rather than immediate clinical implementation. External validation in independent, multicenter, and preferably prospective screening cohorts is needed to assess the model’s generalizability, screening performance, and potential clinical utility.
3.Enzyme-directed Immobilization Strategies for Biosensor Applications
Xing-Bao WANG ; Yao-Hong MA ; Yun-Long XUE ; Xiao-Zhen HUANG ; Yue SHAO ; Yi YU ; Bing-Lian WANG ; Qing-Ai LIU ; Li-He ZHANG ; Wei-Li GONG
Progress in Biochemistry and Biophysics 2025;52(2):374-394
Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.
4.Interproximal tunneling combined with customized connective tissue graft to improve severe papillary defects in the aesthetic zone: a case report and literature review
MAO Yudian ; BAO Han ; AI Luying ; CHEN Weirong ; CHEN Ling ; WU Yun
Journal of Prevention and Treatment for Stomatological Diseases 2025;33(1):50-59
Objective:
To explore the treatment plan for severe papillary defects in the aesthetic zone caused by severe periodontitis, providing a reference for clinical practice.
Methods :
A patient with severe periodontitis leading to severe papillary defects in the upper anterior teeth from 12 to 23 was treated using interdental tunnel technique combined with personalized connective tissue grafting for periodontal plastic surgery, and stable soft tissue augmentation was achieved. Resin restoration was conducted to modify the crown shape of the aesthetic zone teeth, reconstruct white aesthetics, guide the shaping of the gingival papillae, reduce “black triangles,” and enhance the patient’s confidence in smiling.
Results :
The patient’s periodontal condition and the regeneration of soft tissues in the aesthetic zone were good, and the smile aesthetics were restored. After a 3-year follow-up, the gingival morphology, color, and texture were good, and the effect was stable. The literature review indicates that for papillary defects in the aesthetic zone, analysis should be conducted based on the following aspects: whether a defect is present in periodontal hard and soft tissues, crown shape, and the distance from the most apical part of the crown contact area to the top of the alveolar crest. Based on the analysis of aesthetic defects and surgical indications, a personalized treatment plan should be designed.
Conclusion
For patients with obvious papillary defects in the aesthetic zone due to the reduction of periodontal support tissues caused by severe periodontitis, factors such as periodontal hard and soft tissue defects, crown shape, and the distance from the most apical part of the crown contact area to the top of the alveolar crest should be fully considered, and a personalized treatment plan should be formulated after multidisciplinary joint consultation.
5.Angiotensin Ⅱ type 1a receptor knockout ameliorates high-fat diet induced cardiac dysfunction by attenuating ferroptosis
Xiao-xiao YIN ; Jin WANG ; Ai-yun LI ; Li-qing WANG ; Min GOU ; Xiang-ying JIAO
Chinese Pharmacological Bulletin 2025;41(11):2105-2112
Aim To investigate the effect of angioten-sin Ⅱ type 1a receptor(AT1aR)knockout on cardiac dysfunction in rats with obesity and its possible molecu-lar mechanism.Methods SD rats(n=24)were used to generated the whole-body AT1 aR-deficiency rats by sgRNA and the CRISPR/Cas9 system,and the obesity model was constructed by feeding with high-fat diet(HFD).They were divided into four groups:wildtype(WT)and knockout(KO)groups with nor-mal feeding and their respective high-fat diets groups.Color ultrasound diagnostic instrument was uses to e-valuate the cardiac function;oil red O staining was a-dopted to stain the myocardial lipids;RT-PCR was used to detect the levels of GPX4 and Ptgs2 genes in myocardial tissue.Western blot was employed to detect the expression of GPX4,ferritin,Nrf2,HO-1 and NQO1 in rat myocardial tissue.ELISA and other kits were used to determine the lipid contents in serum and myocardium.Results It was found that high-fat feed-ing caused cardiac dysfunction,serum lipid disorders,oxidative stress and ferroptosis in SD rats.However,these changes were attenuated in AT1aR knockout rats fed with high-fat diet.Furthermore,compared with WT-HFD group,KO-HFD rats showed enhanced acti-vation of the Nrf2/HO-1 pathway in the myocardium,reduced ferroptosis,decreased lipid accumulation,and reduced cardiac dysfunction.Conclusion AT1aR knockout can improve HFD-induced cardiac dysfunc-tion by enhancing antioxidant capacity and reducing the degree of ferroptosis.
6.Study on quality standards for Kangjun Xiaoyan preparations
Nan ZHANG ; Shao WANG ; Yun AI ; Yunxia WANG
Drug Standards of China 2025;26(5):493-500
Objective:To establish the quality for Kangjun Xiaoyan preparations.Methods:Rheum officinale Baill,Isatidis indigotica Fort,Miq.Were identified by TLC;microscopic identification method was used to distin-guish Lysimachia christinae Hance and Scutellaria baicalensis Georgi;using maranthoidin B as an indicator compo-nent for the detection of adulteration in Lonicera macranthoides Hand.;the content of chlorogenic acid and baicalin were determined by HPLC.Results:Four types of medicinal herbs in the sample can identify by TLC and negative sample without interference,the examination item for maranthoidin B can accurately determine whether adulterated L.macranthoides is present in the sample;the methodological validation of content determination showed that there was a good linear relationship between chlorogenic acid and baicalin injection mass in the range of 89.8-5 845.4 and 108.2-7 047.0 ng respectively(r=0.999 3 and 0.999 9).The average recoveries were 97.55%and 102.05%with RSDs 1.2%and 1.6%.Conclusion:The established methods were simple,accurate,reliable and reproducible.It can be effectively used for the quality control of Kangjun Xiaoyan preparations.
7.TXNIP gene knockout ameliorates non-alcoholic fatty liver disease by regulating carbon flux of fatty acid synthesis and fatty acid oxidation
Jun-nan ZHAO ; Ai-yun LI ; Wan-zhen SU ; Xiao-xiao YIN ; Tong LI ; Xiang-ying JIAO
Chinese Pharmacological Bulletin 2025;41(8):1524-1530
Aim To investigate the effect of thioredox-in-interacting protein(TXNIP)on non-alcoholic fatty liver disease(NAFLD).Methods Littermate male wild(WT)mice and TXNIP gene whole-body knock-out(KO)mice were randomly divided into two groups:(1)normal diet(ND)group,and(2)The high-fat group,which was fed a high-fat diet(HFD)containing 60%fat for 12 weeks.Serum lipid-related indexes,liver injury indicators and hepatic fat content were detected using commercial kits.The protein lev-els of TXNIP,SLC25A1,SLC13A5,ACLY,CPT1a and PPARα were detected by Western blot.The gene ex-pressions of SLC25A1,SLC13A5 and ACLY were de-tected by RT-PCR.Results High fat diet increased TXNIP protein expression in the liver tissue.Compared with WT-HFD mice,the biochemical indexes in the se-rum and the liver of KO-HFD mice were improved.There was no significant difference in mRNA and pro-tein levels of SLC25A1 between the four groups of mice.For SLC13A5 and ACLY,the mRNA and protein levels of WT-HFD mice were up-regulated compared with WT mice,and these alterations were significantly restored in KO-HFD mice.Besides,compared with WT mice,the protein expressions of the fatty acid oxidation-related protein PPARα and CPT1a proteins in WT-HFD mice decreased,while the protein expressions of PPARα and CPT1 a in KO-HFD mice were significantly enhanced.Conclusion TXNIP gene knockout can improve hepatic steatosis and delay the progression of NAFLD by inhibiting the carbon flux of fatty acid syn-thesis and promoting fatty acid oxidation.
8.Study on the mechanism of different concentrations of simvastatin on regeneration of sciatic nerve injury in rats
Yun-hu LI ; Jun-wei CAO ; Chen LI ; Jing-yu ZHANG ; Ai-she DUN ; Hong-bin WANG
Journal of Regional Anatomy and Operative Surgery 2025;34(9):772-775
Objective To explore the effects of different concentrations of simvastatin on nerve regeneration after sciatic nerve injury.Methods Rats were randomly divided into the normal group,the control group,the low-dose group and the high-dose group,with 3 rats in each group.Except for the normal group,adult rat sciatic nerve crush injury models were established in the other groups.Rats in the normal group and the control group were orally administered with water,while those in the low-dose group and high-dose group were orally administered with 98%simvastatin at dosages of 4 mg/mL and 40 mg/mL,respectively.The sciatic nerve regeneration in rats was evaluated by sciatic function index(SFI),HE staining,luxol fast blue(LFB)staining and immunofluorescence staining,etc.Results The SFI of rats in the high-dose group 7 days and 14 days after surgery were higher than those in the control group(P<0.05);there was no significant difference in SFI of rats between the low-dose group and the control group 7 days and 14 days after surgery(P>0.05).HE staining and LFB staining results showed that compared with the control group,the number of neurons of rats in the high-dose group increased,the nerve fibers and myelin were clearer and denser,and the nerve function was significantly restored;while no significant improvement was observed in the sciatic nerve of rats in the low-dose group.The immunofluorescence staining results showed that compared with the control group,the immunofluorescence intensity in the high-dose group increased,while that in the low-dose group decreased,the differences were statistically significant(P<0.05).Conclusion High-dose simvastatin can promote peripheral nerve regeneration by regulating the expression of M2 macrophages.
9.Diversity, Complexity, and Challenges of Viral Infectious Disease Data in the Big Data Era: A Comprehensive Review.
Yun MA ; Lu-Yao QIN ; Xiao DING ; Ai-Ping WU
Chinese Medical Sciences Journal 2025;40(1):29-44
Viral infectious diseases, characterized by their intricate nature and wide-ranging diversity, pose substantial challenges in the domain of data management. The vast volume of data generated by these diseases, spanning from the molecular mechanisms within cells to large-scale epidemiological patterns, has surpassed the capabilities of traditional analytical methods. In the era of artificial intelligence (AI) and big data, there is an urgent necessity for the optimization of these analytical methods to more effectively handle and utilize the information. Despite the rapid accumulation of data associated with viral infections, the lack of a comprehensive framework for integrating, selecting, and analyzing these datasets has left numerous researchers uncertain about which data to select, how to access it, and how to utilize it most effectively in their research.This review endeavors to fill these gaps by exploring the multifaceted nature of viral infectious diseases and summarizing relevant data across multiple levels, from the molecular details of pathogens to broad epidemiological trends. The scope extends from the micro-scale to the macro-scale, encompassing pathogens, hosts, and vectors. In addition to data summarization, this review thoroughly investigates various dataset sources. It also traces the historical evolution of data collection in the field of viral infectious diseases, highlighting the progress achieved over time. Simultaneously, it evaluates the current limitations that impede data utilization.Furthermore, we propose strategies to surmount these challenges, focusing on the development and application of advanced computational techniques, AI-driven models, and enhanced data integration practices. By providing a comprehensive synthesis of existing knowledge, this review is designed to guide future research and contribute to more informed approaches in the surveillance, prevention, and control of viral infectious diseases, particularly within the context of the expanding big-data landscape.
Big Data
;
Humans
;
Virus Diseases/virology*
;
Artificial Intelligence
10.The Influence of COVID-19 Infection on the Mobilization and Collection of Autologous Peripheral Blood Stem Cells in Patients with Multiple Myeloma.
Guo-Rong WANG ; Guang-Zhong YANG ; Yun LENG ; Yin WU ; Ai-Jun LIU ; Wen-Ming CHEN
Journal of Experimental Hematology 2025;33(2):455-462
OBJECTIVE:
To analyze the effect of COVID-19 infection on the mobilization and collection of autologous peripheral blood stem cells in patients with multiple myeloma.
METHODS:
The general baseline data, treatment factors before mobilization collection, collection status, and treatment overview after collection of autologous peripheral blood stem cells at Beijing Chaoyang Hospital affiliated with Capital Medical University from January 1, 2020 to July 15, 2023 were analyzed.
RESULTS:
269 patients underwent mobilization and collection of autologous peripheral blood stem cells. Among them, 32 cases with COVID-19 infection history (COVID-19 group) and 237 cases without COVID-19 infection history (non-COVID-19 group). In the COVID-19 group, 17 cases were treated with chemotherapy (etoposide)+G-CSF, and 15 cases were treated with plerixafor +G-CSF. In the non-COVID-19 group, 214 cases were treated with chemotherapy +G-CSF, 17 cases were treated with plerixafor +G-CSF, and 6 cases were treated with chemotherapy + plerixafor +G-CSF. The number of CD34+ cells, collection success rate, and excellence rate in the COVID-19 group and the non-COVID-19 group were [5.52 (0.94-26.87) vs 4.80 (0.53-37.20)]×106/kg (P =0.610), (93.8% vs 85.2%) (P =0.275), (62.5% vs 49.4%) (P =0.190), respectively. Among 113 patients mobilized with etoposide +G-CSF, the number of CD34+ cells, success rate, and excellence rate collected from COVID-19 infection (17 cases) and non-COVID-19 infection (96 cases) were [7.54 (2.66-26.87) vs 7.78 (2.26-37.20)]×106/kg (P =0.847), (100.0% vs 100.0%) (no P value), (82.4% vs 86.5%) (P =0.655), respectively. Among 32 patients mobilized by plerixafor +G-CSF, the number of CD34+ cells, success rate and excellence rate of COVID-19 infection (15 cases) and non-COVID-19 infection (17 cases) were [3.82 (0.94-7.27) vs 4.11 (0.53-9.05)]×106/kg (P =0.821), (86.7% vs 88.2%) (P =0.893), (40.0% vs 35.3%) (P =0.784), respectively. In 32 patients with COVID-19 infection, the number of CD34+ cells collected by etoposide +G-CSF (17 cases) and plerixafor +G-CSF (15 cases), as well as the success rate and excellence rate were [7.54 (2.66-26.87) vs 3.82(0.94-7.27)]×106/kg (P =0.004), (100.0% vs 86.7%) (P =0.120), (82.4% vs 40.0%) (P =0.014), respectively. By 2023.7.31, 232 patients (86.2%, 232/269) had received transplantation, including 24 patients in the COVID-19 group and 208 patients in the non-COVID-19 group. The median number of CD34+ cells infused in the two groups was [3.67 (2.50-13.44) vs 3.11(1.12-19.89)]×106/kg (P =0.058), the median days of neutrophil engraftment [11(9-13) vs 11(9-17)] (P =0.674), the median days of platelet engraftment [11(0-23), 12(0-43)] (P =0.279), respectively.
CONCLUSION
The history of COVID-19 infection did not affect the PBSC mobilization, collection and transplantation of patients with myeloma. In patients with COVID-19 infection, the results of chemotherapy mobilization with etoposide seems to be better than that of plerixafor mobilization, but further research is needed to clarify.
Humans
;
COVID-19/complications*
;
Multiple Myeloma/complications*
;
Hematopoietic Stem Cell Mobilization
;
Transplantation, Autologous
;
Granulocyte Colony-Stimulating Factor/therapeutic use*
;
Peripheral Blood Stem Cell Transplantation
;
SARS-CoV-2
;
Middle Aged
;
Peripheral Blood Stem Cells
;
Male
;
Female
;
Cyclams
;
Benzylamines


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