1.Characteristic analysis of nanogel composite system and its application strategies in visualization of diagnostic imaging and therapy
Qian ZHANG ; Fuxia WANG ; Wen WANG ; Kun ZHANG
Chinese Journal of Tissue Engineering Research 2026;30(2):480-488
BACKGROUND:Nanogels can combine the properties of nanoparticles and hydrogels,which have multiple advantages and can play a great role in clinical translation.OJECTIVE:To summarize the self-and cross-linking properties of nanogels,the diagnostic and therapeutic integration strategies they played in a variety of imaging processes,in conjunction with their functional visualization and application properties.METHODS:By searching PubMed,Web of Science,CNKI,and Wanfang databases,English and Chinese search terms were"nanogel,nanohydrogel,imaging,magnetic resonance imaging,fluorescence imaging,ultrasound imaging,photoacoustic imaging,multimodal imaging,therapy,treatment."According to the inclusion criteria,78 articles were finally selected for review.RESULTS AND CONCLUSION:The preparation process of nanogels is significantly affected by their multiple properties and cross-linking mechanisms.Optimization of these properties and mechanisms can help to improve their structural performance and accelerate the translation of their clinical applications.With the trend of integrated diagnosis and treatment,functional visualization of nanogels can effectively image tumors with the help of magnetic resonance imaging,fluorescence imaging,ultrasonography,photoacoustic imaging,and multimodal imaging,which can be of key value in the treatment strategies of various diseases.These findings not only pave the way for improving the preparation methods of nanogels,but also create a robust groundwork for hastening their clinical translation.
2.Statistical approaches to causal inference in environmental epidemiology: Methodological introductions and R implementations
Guiming ZHU ; Wanying LIU ; Yanchao WEN ; Simin HE ; Qian GAO ; Tong WANG
Journal of Environmental and Occupational Medicine 2026;43(2):253-260
Environmental pollution is a significant public health challenge worldwide, and investigating the causal relationship between environmental exposure and population health outcomes is a key objective of environmental epidemiology research. In recent years, the complexity of environmental exposures has increasingly come to the forefront, making it challenging for observational studies that dominate environmental epidemiology to accurately estimate causal effects. Causal inference methods are particularly advantageous in controlling for confounding factors, thus holding great potential in environmental epidemiology research. Researchers can use appropriate causal inference methods to simulate the process of randomization, providing strong support for revealing the causal relationship between environmental exposure and health outcomes. However, there is a lack of reviews on the application of causal inference methods in environmental epidemiology studies in China. Therefore, this study introduced the basic principles of common causal inference statistical methods in environmental epidemiology, summarized the applicable conditions, advantages and disadvantages of various methods, and provided R software implementation codes for these methods, aiming to offer guidance for optimizing research design and practicing causal inference statistical methods.
3.Effect of 12-year-old children s pit and fissure sealants on the health of first permanent molars
LIU Jing, WEI Yonglan, QIAN Wen, HE Xiaoling, QIN Wenlong, WANG Liang
Chinese Journal of School Health 2026;47(1):100-103
Objective:
To assess the effect of 12-year-old children s pit and fissure sealants on the health of first permanent molars, so as to provide evidence for optimizing caries prevention strategies among children.
Methods:
In March 2025, a cluster random sampling method was used to conduct oral examinations on 965 students aged 12 from Chengdu s 2021 Comprehensive Intervention Program for Pediatric Oral Diseases. Data from the Comprehensive Intervention System for Children s Oral Diseases were referenced. Participants were divided into a sealed group ( n =755) and an unsealed group ( n =210) based on whether they had received sealants on their first permanent molars. Chi square test or analysis of variance were used to compare indicators such as caries incidence, new caries detection rate, and new caries mean (DMFT increment) between the two groups
Results:
The sealed group showed significantly lower caries incidence, new caries detection rate, and new caries mean (33.38%, 17.65%, 0.59±1.00) compared to the unsealed group (43.81%, 24.70%, 0.87±1.22)( χ 2/F =7.79, 18.26, 9.55, all P <0.05). However, no significant difference was found in the filled teeth ratio between the two groups (20.38% , 20.16%; χ 2=0.01, P =0.94). In girls, the sealed group exhibited significantly lower caries incidence, new caries detection rate, and new caries mean (36.78%, 20.99%, 0.69± 1.10 ) than the unsealed group (57.55%, 33.52%, 1.15±1.29) ( χ 2/F =14.42, 23.76, 10.92, all P <0.05), whereas no significant differences were observed between boys in the sealed (30.47%, 14.85%, 0.50±0.89) and unsealed groups (29.81%, 16.18%, 0.59± 1.08) ( χ 2/F =0.02, 0.41, 0.74, all P >0.05). Boys had significantly lower new caries detection rates and new caries means than girls in both groups ( χ 2/F =16.20, 6.94; 29.93, 11.84, all P <0.05). In urban areas, the sealed group had lower new caries detection rates and new caries means (19.37%, 0.68±1.04) than the unsealed group (24.66%, 0.90±1.20) ( χ 2/F =6.86, 3.94, both P <0.05). In suburban areas, all indicators for the sealed group (24.71%, 13.77%, 0.42±0.87) were significantly lower than those for the unsealed group (38.81%, 24.77%, 0.82±1.28) ( χ 2/F =5.28, 15.36, 6.00, all P <0.05). Indicators from specialized dental institutions (11.25%, 4.81%, 0.16±0.56) were significantly lower than those from county level or above general hospitals (33.33%, 19.11%, 0.38±1.00) and primary healthcare institutions (37.59%, 19.24%, 0.67±1.05) ( χ 2/F =20.99, 34.31, 21.08 , all P <0.01).
Conclusions
The 12-year-old children s pit and fissure sealants effectively reduce the caries incidence in first permanent molars, particularly showing significant effectiveness in girls and suburban children. Intervention strategies should be optimized according to gender.
4.Establishment of a new predictive model for esophagogastric variceal rebleeding in liver cirrhosis based on clinical features
Wen GUO ; Xuyulin YANG ; Run GAO ; Yaxin CHEN ; Kun YIN ; Qian LI ; Manli CUI ; Mingxin ZHANG
Journal of Clinical Hepatology 2026;42(1):101-110
ObjectiveTo establish a new noninvasive, simple, and convenient clinical predictive model by identifying independent predictive factors for rebleeding after endoscopic therapy in cirrhotic patients with esophagogastric variceal bleeding (EGVB), and to provide a basis for individualized risk assessment and development of clinical intervention strategies. MethodsCirrhotic patients with EGVB who were diagnosed and treated in The First Affiliated Hospital of Xi’an Medical University from September 2018 to October 2023 were enrolled as subjects, and according to whether the patient experienced rebleeding within 1 year after endoscopic therapy, they were divided into rebleeding group with 93 patients and non-rebleeding group with 84 patients. Clinical data were collected and analyzed. The independent samples t-test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups; the chi-square test was used for comparison of categorical data between two groups. A Logistic model was established based on the results of the univariate and multivariate analyses, and the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were used to assess the accuracy of the model. R software was used to visualize the model by plotting a nomogram, and the Bootstrap method was used for internal validation of the model. ResultsThe multivariate analysis showed that red blood cell count (RBC), cholinesterase (ChE), alkaline phosphatase (ALP), albumin (Alb), thrombin time (TT), portal vein trunk diameter, sequential therapy, and primary prevention were independent predictive factors for rebleeding. Based on the results of the multivariate analysis, a logistic model was established as logit(P)=-0.805-1.978×(RBC)+0.001×(ChE)-0.020×(ALP)-0.314×(Alb)+0.567×(TT)+0.428×(portal vein trunk diameter)-2.303×[sequential therapy (yes=1, no=0)]-2.368×[primary prevention (yes=1, no=0)]. The logistic model (AUC=0.928, 95% confidence interval [CI]: 0.893—0.964, P<0.001) had a better performance in predicting rebleeding than MELD score (AUC=0.603, 95%CI: 0.520—0.687, P=0.003), Child-Pugh class (AUC=0.650, 95%CI: 0.578—0.722, P=0.001), and FIB-4 index (AUC=0.587, 95%CI: 0.503—0.671, P=0.045). The model had an optimal cut-off value of 0.607, a sensitivity of 0.817, and a specificity of 0.817. Internal validation confirmed that the model had good predictive performance and accuracy. ConclusionSequential therapy, implementation of primary prevention, an increase in RBC, and an increase in Alb are protective factors against rebleeding, while prolonged TT and widened main portal vein diameter are risk factors. The logistic model based on these independent predictive factors can predict rebleeding and thus holds promise for clinical application.
5.Characteristic analysis of nanogel composite system and its application strategies in visualization of diagnostic imaging and therapy
Qian ZHANG ; Fuxia WANG ; Wen WANG ; Kun ZHANG
Chinese Journal of Tissue Engineering Research 2026;30(2):480-488
BACKGROUND:Nanogels can combine the properties of nanoparticles and hydrogels,which have multiple advantages and can play a great role in clinical translation.OJECTIVE:To summarize the self-and cross-linking properties of nanogels,the diagnostic and therapeutic integration strategies they played in a variety of imaging processes,in conjunction with their functional visualization and application properties.METHODS:By searching PubMed,Web of Science,CNKI,and Wanfang databases,English and Chinese search terms were"nanogel,nanohydrogel,imaging,magnetic resonance imaging,fluorescence imaging,ultrasound imaging,photoacoustic imaging,multimodal imaging,therapy,treatment."According to the inclusion criteria,78 articles were finally selected for review.RESULTS AND CONCLUSION:The preparation process of nanogels is significantly affected by their multiple properties and cross-linking mechanisms.Optimization of these properties and mechanisms can help to improve their structural performance and accelerate the translation of their clinical applications.With the trend of integrated diagnosis and treatment,functional visualization of nanogels can effectively image tumors with the help of magnetic resonance imaging,fluorescence imaging,ultrasonography,photoacoustic imaging,and multimodal imaging,which can be of key value in the treatment strategies of various diseases.These findings not only pave the way for improving the preparation methods of nanogels,but also create a robust groundwork for hastening their clinical translation.
6.Clinical features and multimodal quantitative radiological features of primary liver cancer patients with different traditional Chinese medicine syndrome types
Feng WU ; Muqing LUO ; Wantingting WEN ; Ziwei CAI ; Yinqi LIU ; Jian XIANG ; Xiaona ZHOU ; Qian GUO ; Kun ZHANG
Journal of Clinical Hepatology 2026;42(5):1093-1100
ObjectiveTo investigate the association of the traditional Chinese medicine (TCM) syndrome types of primary liver cancer (PLC) with clinical features and multimodal quantitative radiological features on computed tomography (CT) and magnetic resonance imaging (MRI), and to provide a reference for the objectification of TCM syndrome differentiation and precise diagnosis and treatment. MethodsA retrospective analysis was performed for the clinical data of 312 patients who were diagnosed with PLC in The First Affiliated Hospital of Hunan University of Chinese Medicine from March 2020 to June 2025, and according to the TCM syndrome type, they were divided into stagnation of liver Qi group with 40 patients, stagnation of liver Qi and spleen deficiency group with 109 patients, Qi stagnation and blood stasis group with 62 patients, dampness-heat toxin amassment group with 81 patients, and liver-kidney Yin deficiency group with 20 patients. Clinical features and multimodal quantitative radiological features were compared between the patients with different TCM syndrome types. A one-way analysis of variance was used for comparison of normally distributed continuous data between multiple groups, and the least significant difference t-test was used for further comparison between two groups; the Kruskal-Wallis H test was used for comparison of non-normally distributed continuous data between multiple groups, and the Dunn’s multiple test was used for further comparison between two groups; the chi-square test was used for comparison of categorical data between groups, and the Bonferroni method was used for further comparison between two groups. ResultsThere were significant differences between the patients with different TCM syndrome types in China liver cancer staging (CNLC), Child-Pugh class, alanine aminotransferase, aspartate aminotransferase, albumin, direct bilirubin, total bilirubin, prothrombin time, neutrophil, and albumin-bilirubin score (all P<0.05). In the stagnation of liver Qi group, the patients with Child-Pugh class A accounted for 75.00%; among the patients with CNLC stage I PLC, the patients with stagnation of liver Qi accounted for 60.00%, and those with Qi stagnation and blood stasis syndrome accounted for 59.68%, while among the patients with CNLC stage IV PLC, the distribution proportion of dampness-heat toxin amassment (27.16%) and liver-kidney Yin deficiency (30.00%) was significantly higher than that of stagnation of liver Qi (2.50%) (all P<0.05). Radiological examination showed that there were significant differences between the patients with different TCM syndrome types in the number of tumors, ascites, venous tumor thrombus, maximum tumor diameter, intrahepatic metastasis, and lymph node metastasis in the hepatic hilar and retroperitoneal regions (all P<0.05). Compared with the patients with stagnation of liver Qi, the patients with liver depression and spleen deficiency or liver-kidney Yin deficiency were more likely to develop intrahepatic metastasis; the patients with liver depression and spleen deficiency, dampness-heat toxin amassment, or liver-kidney Yin deficiency were more likely to develop lymph node metastasis in the hepatic hilar and retroperitoneal regions; the patients with liver-kidney Yin deficiency were more likely to experience multiple tumors; the patients with liver depression and spleen deficiency or dampness-heat toxin amassment were more likely to develop ascites (all P<0.05). Compared with the patients with Qi stagnation and blood stasis syndrome, the patients with liver depression and spleen deficiency had a significantly longer maximum tumor diameter and a significantly higher proportion of patients with venous tumor thrombus (both P<0.05). Furthermore, among the 184 patients with MRI diffusion-weighted imaging sequences, the patients with dampness-heat toxin amassment or Qi stagnation and blood stasis syndrome had significantly higher ADC values and relative ADC values than those with stagnation of liver Qi (all P<0.05). ConclusionThere are significant differences in CT/MRI radiological features and clinical features between PLC patients with different TCM syndrome types, among whom the patients with liver depression and spleen deficiency, dampness-heat toxin amassment, and liver-kidney Yin deficiency tend to exhibit progressive radiological features, and those with dampness-heat toxin amassment or Qi stagnation and blood stasis syndrome tend to have higher ADC values. These findings provide an objective basis for TCM syndrome differentiation in PLC.
7.Exercise Intervention Alleviates Diabetic Sarcopenia by Regulating Lipid Metabolic Reprogramming: Mechanisms and Strategies
Meng-Lin LÜ ; Bao-Wen ZHANG ; Qian-Qian REN ; Xian-Juan KOU
Progress in Biochemistry and Biophysics 2026;53(8):2025-2040
Diabetic sarcopenia (DS) is a common but often ignored skeletal muscle complication in individuals with diabetes mellitus. It is characterized by progressive loss of skeletal muscle mass, reduced muscle strength, and impaired physical performance, which may further increase the risk of falls, disabilities, metabolic disorders, and adverse clinical outcomes. Traditionally, DS has been attributed mainly to hyperglycemia, insulin resistance, aging-related muscle decline, and chronic complications of diabetes. However, increasing evidence suggests that lipid metabolic disturbance and pathological lipid metabolic reprogramming are not merely secondary consequences of diabetes, but may actively participate in the initiation and progression of DS. Under diabetic conditions, impaired fatty acid uptake, transport, oxidation, and storage disrupt skeletal muscle metabolic homeostasis, leading to ectopic lipid deposition and accumulation of lipotoxic intermediates. These lipid-derived metabolites can aggravate insulin resistance, impair mitochondrial energy production, enhance oxidative stress, activate chronic low-grade inflammation, and disturb protein synthesis and degradation balance, thereby accelerating skeletal muscle atrophy and functional decline. Lipid metabolic dysregulation may also interact with multiple pathological processes involved in DS, including mitochondrial dysfunction, inflammatory signaling, oxidative damage, impaired autophagy, and gut microbiota imbalance. These mechanisms do not occur independently; instead, they form a complex bidirectional vicious cycle with diabetes-related metabolic disorders. Specifically, mitochondrial dysfunction reduces fatty acid oxidative capacity, which further promotes lipid accumulation and lipotoxicity. Inflammatory activation can impair insulin signaling and muscle protein metabolism, while lipid overload may in turn amplify inflammatory responses. Similarly, gut microbiota dysbiosis and altered microbial metabolites may influence systemic inflammation, lipid metabolism, and skeletal muscle homeostasis. Therefore, lipid metabolic reprogramming provides an important mechanistic perspective for understanding the progression of DS from metabolic disturbance to structural and functional muscle impairment. Exercise intervention is an effective and clinically feasible non-pharmacological strategy for the prevention and management of DS. Both aerobic exercise and resistance training have been shown to improve insulin sensitivity, enhance fatty acid oxidation, increase mitochondrial biogenesis, reduce ectopic lipid deposition, and attenuate lipotoxic metabolite accumulation. These adaptations not only improved glucose and lipid metabolism, but also increased the preservation of muscle mass, muscle strength, and physical function. Moreover, combined exercise strategies may provide complementary benefits by integrating the metabolic advantages of aerobic exercise with the anabolic and functional effects of resistance training. Based on analyses of publicly available datasets and literature evidences, this review systematically summarizes the role of lipid metabolic disorders in the pathogenesis of DS, with particular attention to the molecular mechanisms linking lipid dysregulation to insulin resistance, chronic inflammation, oxidative stress, mitochondrial dysfunction, and gut microbiota disturbance. Furthermore, this review discusses the potential mechanisms by which exercise intervention improves DS through the regulation of lipid metabolic reprogramming, and outlines exercise prescription strategies in terms of modality, intensity, frequency, and duration. Understanding the interaction between lipid metabolism and skeletal muscle dysfunction may provide new theoretical evidence for early identification, mechanistic research, and precision exercise therapy in DS. Overall, targeting pathological lipid metabolic reprogramming through exercise intervention represents a promising and clinically actionable approach for improving muscle health and prognosis in individuals with DS.
8.Diagnosis and treatment of cirrhotic portal hypertension with spontaneous portosystemic shunt: Current status and prospects
Yaxin CHEN ; Wen GUO ; Kaige LIU ; Qian LI ; Mingxin ZHANG
Journal of Clinical Hepatology 2025;41(1):176-182
Liver cirrhosis is the terminal stage of various chronic liver diseases, with the main clinical manifestation of portal hypertension, which can lead to spontaneous portosystemic shunt (SPSS). SPSS is very common in clinical practice and is closely associated with the prognosis of patients. This article summarizes the recent studies in the clinical significance of cirrhotic portal hypertension with SPSS, the controversies in studies, and the current status and future prospects and challenges of treatment, in order to provide a reference for the standardized diagnosis and treatment of portal hypertension.
9.Application of Recombinant Collagen in Biomedicine
Huan HU ; Hong ZHANG ; Jian WANG ; Li-Wen WANG ; Qian LIU ; Ning-Wen CHENG ; Xin-Yue ZHANG ; Yun-Lan LI
Progress in Biochemistry and Biophysics 2025;52(2):395-416
Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.
10.Clinical Study on the Treatment of 70 Cases Chronic Atrophic Gastritis with Intestinal Metaplasia Using Xianglian Huazhuo Granules (香连化浊颗粒):A Randomized,Double-Blind,Placebo-Controlled Trial
Ziyu LI ; Maopeng ZHANG ; Wen ZHAO ; Wei LI ; Shiyun SHENG ; Haiyan BAI ; Qian YANG
Journal of Traditional Chinese Medicine 2025;66(5):473-479
ObjectiveTo observe the clinical efficacy and possible mechanisms of Xianglian Huazhuo Granules (香连化浊颗粒, XHG) in the treatment of chronic atrophic gastritis with intestinal metaplasia. MethodsA total of 140 patients with chronic atrophic gastritis and intestinal metaplasia were randomly divided into a treatment group and a control group, with 70 cases in each group. The treatment group received 12.5 g of XHG orally, twice daily. The control group received 12.5 g of placebo orally, twice daily. Both groups were treated for 6 months. The traditional Chinese medicine (TCM) symptom scores, pathological types, serum tumor markers of the digestive system, and serum bile acids (TBA), interleukin-23 (IL-23), and Dickkopf-related protein 1 (DKK-1) levels were observed before and after treatment. Safety indicators and adverse events were recorded. After treatment, TCM syndrome efficacy and pathological types were evaluated, and patients were followed up for 18 months with gastric endoscopy and pathological results, which were compared with the results after treatment finished. ResultsTwo patients dropped out in the control group, and a total of 168 cases were included in the final analysis, 70 in the treatment group and 68 in the control group. The treatment group showed a significant reduction in TCM symptom scores, serum TBA, IL-23, and DKK-1 levels, and a significant increase in alpha-fetoprotein (AFP), carbohydrate antigen 125 (CA125), carbohydrate antigen 199 (CA199) levels; in the control group, carcinoembryonic antigen (CEA), CA125, CA199 levels significantly increased (P<0.05 or P<0.01); and carbohydrate antigen 242 (CA242) level in both the treatment group and the control group decreased significantly (P<0.01). The treatment group had lower TCM symptom scores and lower levels of serum TBA, IL-23, and DKK-1 compared to the control group (P<0.05). The effective rate for TCM syndrome efficacy in the treatment group was 80.00% (56/70), significantly higher than the 20.59% (14/68) in the control group (P < 0.05). The effective rate for pathological classification in the treatment group was 72.73% (8/11) for mixed intestinal metaplasia, significantly better than 46.15% (6/13) in the control group (P<0.05). No adverse events were reported in either group. Among 40 patients who had a follow-up endoscopy after one year, 21 were from the treatment group, of whom 11 showed reduced intestinal metaplasia, 9 showed no significant changes, and 1 had worsened; while 19 patients in the control group had 4 with reduced intestinal metaplasia, 13 with no significant changes, and 2 with worsened conditions. No cancer was detected in either group. The treatment group showed significantly better improvement in intestinal metaplasia on follow-up gastric endoscopy pathology than the control group (P<0.05). ConclusionXHG can significantly improve the clinical symptoms in patients with chronic atrophic gastritis and intestinal metaplasia and reduce the degree of mixed intestinal metaplasia. The mechanism may involve lowering serum TBA, DKK-1, and IL-23 levles, thus delaying the progression from inflammation to cancer.

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