1.Construction of Organoid-on-a-chip and Its Applications in Biomedical Fields
Rui-Xia LIU ; Jing ZHANG ; Xiao LI ; Yi LIU ; Long HUANG ; Hong-Wei HOU
Progress in Biochemistry and Biophysics 2026;53(2):293-308
Organoid-on-a-chip technology represents a promising interdisciplinary advancement that merges two cutting-edge biomedical platforms: stem cell-derived organoids and microfluidics-based organ-on-a-chip systems. Organoids are self-organizing three-dimensional (3D) cell cultures that mimic the key structural and functional features of in vivo organs. However, traditional organoid culture systems are often static, lacking dynamic environmental cues and suffering from limitations such as batch-to-batch variability, low stability, and low throughput. Organ-on-a-chip platforms, by contrast, utilize microfluidic technologies to simulate the dynamic physiological microenvironment of human tissues and organs, enabling more controlled cell growth and differentiation. By integrating the advantages of organoids and organ-on-a-chip technologies, organoid-on-a-chip systems transcend the limitations of conventional 3D culture models, offering a more physiologically relevant and controllable in vitro platform. In organoid-on-a-chip systems, stem cells or pre-formed organoids are cultured in micro-engineered environments that mimic in vivo conditions, enabling precise control over fluid flow, mechanical forces, and biochemical cues. Specifically, these platforms employ advanced strategies including bio-inspired 3D scaffolds for structural support, precise spatial cell patterning via 3D bioprinting, and integrated biosensors for real-time monitoring of metabolic activities. These synergistic elements recreate complex extracellular matrix signals and ensure high structural fidelity. Based on structural complexity, organoid-on-a-chip systems are classified into single-organoid and multi-organoid types, forming a trajectory from unit biomimicry to systemic simulation. Single-organoid chips focus on highly biomimetic units by integrating vascular, immune, or neural functions. Multi-organoid chips simulate inter-organ crosstalk and systemic homeostasis, advancing complex disease modeling and PK/PD evaluation. This emerging technology has demonstrated broad application potential in multiple fields of biomedicine. Organoid-on-a-chip systems can recapitulate organ developmentin vitro, facilitating research in developmental biology. They mimic organ-specific physiological activities and mechanisms, showing promising applications in regenerative medicine for tissue repair or replacement. In disease modeling, they support the reconstruction of models for neurodegenerative, inflammatory, infectious, metabolic diseases, and cancers. These platforms also enable in vitro drug testing and pharmacokinetic studies (ADME). Patient-derived chips preserve genetic and pathological features, offering potential for precision medicine. Additionally, they reduce species differences in toxicology, providing human-relevant data for environmental, food, cosmetic, and drug safety assessments. Despite progress, organoid-on-a-chip systems face challenges in dynamic simulation, extracellular matrix (ECM) variability, and limited real-time 3D imaging, requiring improved materials and the integration of developmental signals. Current bottlenecks also include the high technical threshold for automation and the lack of standardized validation frameworks for regulatory adoption. Meanwhile, the concept of a “human-on-a-chip” has been proposed to mimic whole-body physiology by integrating multiple organoid modules. This approach enables systemic modeling of drug responses and toxicity, with the potential to reduce animal testing and revolutionize drug development. Future advancements in bio-responsive hydrogels and flexible biosensors will further empower these platforms to bridge the gap between bench-side research and personalized clinical interventions. In conclusion, organoid-on-a-chip technology offers a transformative in vitro model that closely recapitulates the complexity of human tissues and organ systems. It provides an unprecedented platform for advancing biomedical research, clinical translation, and pharmaceutical innovation. Continued development in biomaterials, microengineering, and analytical technologies will be essential to unlocking the full potential of this powerful tool.
2.Construction of Organoid-on-a-chip and Its Applications in Biomedical Fields
Rui-Xia LIU ; Jing ZHANG ; Xiao LI ; Yi LIU ; Long HUANG ; Hong-Wei HOU
Progress in Biochemistry and Biophysics 2026;53(2):293-308
Organoid-on-a-chip technology represents a promising interdisciplinary advancement that merges two cutting-edge biomedical platforms: stem cell-derived organoids and microfluidics-based organ-on-a-chip systems. Organoids are self-organizing three-dimensional (3D) cell cultures that mimic the key structural and functional features of in vivo organs. However, traditional organoid culture systems are often static, lacking dynamic environmental cues and suffering from limitations such as batch-to-batch variability, low stability, and low throughput. Organ-on-a-chip platforms, by contrast, utilize microfluidic technologies to simulate the dynamic physiological microenvironment of human tissues and organs, enabling more controlled cell growth and differentiation. By integrating the advantages of organoids and organ-on-a-chip technologies, organoid-on-a-chip systems transcend the limitations of conventional 3D culture models, offering a more physiologically relevant and controllable in vitro platform. In organoid-on-a-chip systems, stem cells or pre-formed organoids are cultured in micro-engineered environments that mimic in vivo conditions, enabling precise control over fluid flow, mechanical forces, and biochemical cues. Specifically, these platforms employ advanced strategies including bio-inspired 3D scaffolds for structural support, precise spatial cell patterning via 3D bioprinting, and integrated biosensors for real-time monitoring of metabolic activities. These synergistic elements recreate complex extracellular matrix signals and ensure high structural fidelity. Based on structural complexity, organoid-on-a-chip systems are classified into single-organoid and multi-organoid types, forming a trajectory from unit biomimicry to systemic simulation. Single-organoid chips focus on highly biomimetic units by integrating vascular, immune, or neural functions. Multi-organoid chips simulate inter-organ crosstalk and systemic homeostasis, advancing complex disease modeling and PK/PD evaluation. This emerging technology has demonstrated broad application potential in multiple fields of biomedicine. Organoid-on-a-chip systems can recapitulate organ developmentin vitro, facilitating research in developmental biology. They mimic organ-specific physiological activities and mechanisms, showing promising applications in regenerative medicine for tissue repair or replacement. In disease modeling, they support the reconstruction of models for neurodegenerative, inflammatory, infectious, metabolic diseases, and cancers. These platforms also enable in vitro drug testing and pharmacokinetic studies (ADME). Patient-derived chips preserve genetic and pathological features, offering potential for precision medicine. Additionally, they reduce species differences in toxicology, providing human-relevant data for environmental, food, cosmetic, and drug safety assessments. Despite progress, organoid-on-a-chip systems face challenges in dynamic simulation, extracellular matrix (ECM) variability, and limited real-time 3D imaging, requiring improved materials and the integration of developmental signals. Current bottlenecks also include the high technical threshold for automation and the lack of standardized validation frameworks for regulatory adoption. Meanwhile, the concept of a “human-on-a-chip” has been proposed to mimic whole-body physiology by integrating multiple organoid modules. This approach enables systemic modeling of drug responses and toxicity, with the potential to reduce animal testing and revolutionize drug development. Future advancements in bio-responsive hydrogels and flexible biosensors will further empower these platforms to bridge the gap between bench-side research and personalized clinical interventions. In conclusion, organoid-on-a-chip technology offers a transformative in vitro model that closely recapitulates the complexity of human tissues and organ systems. It provides an unprecedented platform for advancing biomedical research, clinical translation, and pharmaceutical innovation. Continued development in biomaterials, microengineering, and analytical technologies will be essential to unlocking the full potential of this powerful tool.
3.Development of A High-performance Rectangular Ion Trap for Multi-reflection Time-of-Flight Mass Spectrometer
Xiao-Xia CHEN ; Yi REN ; Qi HUANG ; Da-Jun XIANG ; Chang-Wei LI ; Yi HONG ; Lei LI ; Zheng-Xu HUANG ; Mei LI ; Jing-Wei XU ; Zhen ZHOU
Chinese Journal of Analytical Chemistry 2025;53(1):38-46
As a new generation of time-of-flight mass spectrometry,multiple-reflection time-of-flight mass spectrometry(MR-TOF-MS)has been increasingly applied in the fields such as nuclear physics,chemistry,and biology due to its ultra-high resolution and rapid analysis capabilities.However,the analytical performance of MR-TOF-MS largely depends on the ion bunch state entering the mass analyzer.In this study,a rectangular ion trap(RIT)was developed,designed and processed using printed circuit board technology,as an ion accumulating and focusing device for MR-TOF mass analyzer.Compared to traditional ion traps composed of two sets of planar electrodes,this RIT had higher voltage utilization efficiency,resulting in more efficient ion collection and focusing.The ions were cooled to a sufficiently small bunch for precise mass measurement with MR-TOF-MS mass spectrometry in only 1 ms of cooling time in the RIT,then orthogonally ejected to the MR-TOF mass spectrometer for mass analysis.Experimental results indicated that the working cycle,ion flux,and ion focusing state of the RIT fully met the requirements of the MR-TOF mass analyzer.When coupled with the MR-TOF mass analyzer,the RIT enabled MR-TOF-MS to achieve a mass resolution of 1.5×105.
4.Detection of Ketamine and Norketamine Using an Aptamer-Functionalized Gra-phene Oxide Fluorescent Sensor
Li-Xia WEI ; Bo LIU ; Xiao-Yuan YANG ; Xi ZHANG ; Yi-Feng LAN ; Chao ZHANG ; Juan JIA ; Dan ZHANG ; Zhi-Wen WEI ; Ke-Ming YUN ; Zhe CHEN
Journal of Forensic Medicine 2025;41(4):326-339
Objective To construct an aptamer-functionalized carboxylated graphene oxide(CGO)fluo-rescent sensor to achieve highly sensitive and specific detection of ketamine(KET)and its metabolite norketamine(NK)using an aptamer capable of simultaneously recognizing KET and NK.Methods A specific aptamer for simultaneous recognition of KET and NK was screened using graphene oxide-sys-tematic evolution of ligand by exponential enrichment(GO-SELEX)and molecular docking tech-niques.The aptamer,labeled with Cy5 fluorescence,was chemically conjugated to CGO to construct an aptamer-functionalized CGO fluorescent sensor.By optimizing detection conditions,including the mass concentration of CGO,aptamer concentration,reaction temperature,and incubation time,quantita-tive analysis of the target analytes was achieved using the ratio of fluorescence intensity changes be-fore and after target addition.The stability of the sensor in biological matrices was evaluated by moni-toring fluorescence intensity changes over incubation time in blank blood and urine,in comparison with the traditional physical adsorption-based CGO fluorescent sensor.Spiked recovery experiments in blank blood and urine were conducted to compare performance with that of HPLC-MS/MS.Results A specific aptamer A5 was selected and chemically conjugated with CGO to construct the aptamer-functionalized CGO fluorescent sensor.Under optimized conditions,the proposed fluorescent sensor ex-hibited a linear detection range of 1.0-5.0 ng/mL for KET,with a limit of detection(LOD)of 0.86 ng/mL;while for NK,the linear detection range was 1.0-5.0 ng/mL,with an LOD of 0.70 ng/mL.Com-pared with the CGO fluorescent sensor constructed via physical adsorption,this sensor demonstrated greater stability in blood and urine.The spiked recovery rates of KET and NK in blank blood and urine ranged from 81.50%to 110.03%,exhibiting detection performance comparable to that of HPLC-MS/MS.Conclusion The aptamer screening method offers a novel approach for selecting aptamers tar-geting drugs and their metabolites.The constructed aptamer-functionalized CGO fluorescent sensor pro-vides an efficient and reliable strategy for the high-performance detection of KET and NK.
5.Effect of HSYA on LCN2-induced iron death of HT22 cells and its mechanism based on SLC7A11/GPX4 signaling pathway
Meng-wei RONG ; Cun-yan DAN ; Tian-qing XIA ; Yi YANG ; Xiu LOU ; Chen-xiang JI ; Bao-guo XIAO ; Cun-gen MA ; Li-juan SONG
Chinese Pharmacological Bulletin 2025;41(11):2097-2105
Aim To explore the effect of hydroxysafflor yellow A(HSYA)on lipocalin 2(LCN2)-induced fer-roptosis in HT22 cells and the related mechanism.Methods Thirty male Sprague-Dawley(SD)rats were used to establish the middle cerebral artery occlu-sion/reperfusion(MCAO/R)model by the suture method.The rats were randomly divided into the Sham group,the MCAO/R group,and the MCAO/R+HSYA group.The infarct area was measured by TTC staining,and the degree of neurological deficit was evaluated by the Z-Longa scoring method.The expressions of LCN2 and 24P3R in brain tissues were detected by Western blot.LCN2 protein was added to HT-22 cells,and the cells were divided into the normal group,the LCN2 group,and the LCN2+HSYA group.The optimal con-centration of LCN2-induced neuronal ferroptosis was screened by LDH assay and Western blot,and the ex-pression levels of ferritin,FPN1,GPX4,SLC7A11,COX2,and 24P3R were detected.LCN2 was knocked down by siRNA transfection,and the expressions of GPX4 and ferritin were detected.The contents of glu-tathione(GSH),malondialdehyde(MDA),GPX4,and Fe2+were determined by colorimetry,and the expres-sion of GPX4 was detected by immunofluorescence.The binding force between HSYA and LCN2 was ana-lyzed by molecular docking technology.Results Ani-mal experiments showed that HSYA could reduce the cerebral infarction area and decrease the neurological function score of MCAO/R rats.Compared with the sham group,the levels of LCN2 and 24P3R increased in the MCAO/R group,while HSYA inhibited their ex-pressions.Cell experiments showed that the optimal concentration of LCN2 to induce ferroptosis in HT22 cells was 2 μmol·L-1.After knocking down LCN2 by siRNA transfection,compared with the LCN2 group,the expression levels of GPX4 and ferritin in the siLCN2 group increased significantly.Compared with the nor-mal group,the expressions of SLC7A11,GPX4,FPN1,ferritin,and GSH in the LCN2 group decreased signifi-cantly,while the concentration of Fe2+,and the expres-sions of MDA,COX2,and 24P3R increased.HSYA could increase the expressions of SLC7A11,GPX4,FPN1,ferritin,and GSH,reduce the contents of Fe2+and MDA,and inhibit the expressions of COX2 and 24P3R.Molecular docking showed that the binding en-ergy between HSYA and LCN2 was-8.0 kJ·mol-1.Conclusion HSYA can inhibit LCN2-induced ferrop-tosis in HT22 cells through the SLC7A11/GPX4 signa-ling pathway.
6.A clinical study on shunt reduction in the treatment of refractory hepatic encephalopathy after transjugular intrahepatic portosystemic shunt
Nianjun XIAO ; Wenjuan LYU ; Baojie WEI ; Zhibo XIA ; Lang WU ; Kai AN ; Zheyi HAN ; Shoubin NING ; Jianguo CHU
Chinese Journal of Digestion 2025;45(7):457-461
Objective:To explore the safety and efficacy of shunt reduction using the Interlock-35 fibered interlocking detachable coil (IDC) occlusion system in the treatment of refractory hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS).Methods:From August 2022 to December 2023, at the Department of Gastroenterology of the Air Force Medical Center, the clinical data of patients with refractory HE after TIPS who were treated with shunt reduction using the Interlock-35 fibered IDC occlusion system were retrospectively collected, which included portal vein pressure gradient (PVPG), HE grades, blood ammonia levels, prothrombin time (PT), liver function parameters, and other related indicators. The primary indicators related to the efficacy of the shunt reduction included symptom improvement, and changes in PVPG, blood ammonia levels, and Child-Pugh score. The safety of shunt reduction was analyzed based on the incidence of complications such as gastrointestinal bleeding and ascites during the follow-up period. Paired t-test was used for statistical analysis. Results:A total of 21 patients were enrolled. Prior to shunt reduction, there were 5 cases with HE of grade 3 and 16 cases with HE of grade 2. Before operation, the blood ammonia was (103.14±27.69) mol/L; and the liver function Child-Pugh grade of 1 case was classified as grade A, 16 cases as grade B, and 4 cases as grade C. Shunt reduction was performed between 7 and 1 879 d, with a median time of 99 (54, 806) d after TIPS. The procedure was technically successful in all patients, with a total of 25 coils implanted. Before shunt reduction, the PVPG was (14.02±5.28) cmH 2O (1 cmH 2O=0.098 kPa), after shunt reduction procedure, the PVPG increased to (25.05±6.04) cmH 2O, and the difference was statistically significant ( t=-11.26, P<0.001). After operation, 16 patients returned to the hospital for follow-up examinations, with a median follow-up time of 114 (46, 195) d, the blood ammonia levels, PT, and Child-Pugh scores during the follow-up were all lower than those before operation ((78.19±27.85) μmol/L vs. (105.00±30.53) μmol/L, (14.09±1.65) s vs. (15.41±2.35) s, and 6.88±1.59 vs. 8.13±1.75, respectively), and the differences were statistically significant ( t=2.23, 3.23, and 2.61; P=0.040, <0.001, =0.020). There was no statistically significant in PVPG between during follow-up and immediately post-procedure ((28.91±6.20) cmH 2O vs. (25.22±5.92) cmH 2O, P>0.05). During the follow-up period, HE symptoms disappeared in 12 patients among the 16 patients who returned to hospital for follow-up, however gastrointestinal bleeding occurred in 5 patients and ascites occurred in 3 patients; additionally, 4 patients experienced intermittent HE symptoms (grade 1 in 3 cases, grade 2 in 1 case). After operation, 5 patients were followed up via telephone, among them, 3 patients died, and 2 patients experienced intermittent HE (grade 1) which could be spontaneously restored with dietary adjustments and(or) medication. Conclusions:Interlock-35 fibered IDC occlusion system for shunt reduction is a feasible and effective treatment for refractory HE after TIPS. It can effectively improve symptoms and decrease liver function score. After shunt reduction, early follow-up and adjustment of flow reduction can help reduce the occurrence of severe complications.
7.Study on protection of cerebral ischemia-reperfusion injury by HSYA activated neuronal autophagy based on SIRT1
Lijuan SONG ; Ruheng WEI ; Yaoyao DAI ; Jianlin HUA ; Mengwei RONG ; Cunyan DAN ; Chunli WEN ; Tianqing XIA ; Ce ZHANG ; Baoguo XIAO ; Cungen MA
Chinese Journal of Immunology 2025;41(6):1350-1357
Objective:To investigate effect and mechanism of hydroxysafflor yellow A(HSYA)activating neuronal autophagy on cerebral ischemia-reperfusion injury through a combination of in vitro and in vivo experiments.Methods:SD rat MCAO/R model was established by improved suture method.Rats were randomly divided into sham surgery(Sham)group,MCAO/R group and MCAO/R+HSYA group,following indicators were detected to determine extent of cerebral ischemia-reperfusion nerve damage:Z-Longa neu-rological function score was detected,TTC staining to measure cerebral infarction area,and TUNEL staining to measure cell apopto-sis;Western blot was used to detect protein expressions of autophagy related markers LC3,Beclin1,P62 and SIRT1 in rat brain tis-sue;immunofluorescence staining was used to observe expression of LC3 co-localization with neurons.OGD/R injury model of SH-SY5Y cells was established and randomly divided into Normal group,OGD/R group,OGD/R+HSYA group,OGD/R+SIRT1 inhibitor(EX-527)group and OGD/R+EX-527+HSYA group.Western blot was used to detect protein expressions of LC3,Beclin1,P62 and SIRT1.Results:Compared with Sham group,model group rats showed impaired neurological function,significantly increased neu-robehavioral scores,widespread cerebral infarction,significantly increased neuronal cell apoptosis,significantly increased autophagy related protein Beclin1 expression and LC3-Ⅱ/LC3-Ⅰ,significantly decreased P62 expression,significantly increased LC3/NeuN co-stained cells,and decreased SIRT1 expression;compared with model group,HSYA intervention group showed a significant decrease in neurological functional scores,a significant reduction in cerebral infarction area,a significant decrease in neuronal cell apoptosis,a further increase in Beclin1 expression and LC3-Ⅱ/LC3-Ⅰ,a further decrease in P62 expression,number of LC3/NeuN and P62/NeuN co-stained cells also increased,and SIRT1 expression significantly increased.Expression trends of Beclin1,LC3-Ⅱ/LC3-Ⅰ,P62 and SIRT1 of cells between normal group,model group and HSYA intervention group were same as animal experiment;compared with model group,expressions of SIRT1,Beclin1 and LC3-Ⅱ/LC3-Ⅰ in OGD/R+EX-527 group were significantly reduced,while expression of P62 was significantly increased;compared with OGD/R+EX-527 group,there was no significant change in SIRT1 expression in OGD/R+EX-527+HSYA group,LC3-Ⅱ/LC3-Ⅰ and Beclin1 expression were significantly increased,and P62 expres-sion was significantly decreased.Conclusion:HSYA can significantly improve neurological deficits in rats after cerebral ischemia-reperfusion,reduce cerebral infarction area,and decrease neuronal cell apoptosis rate,whose neuroprotective effect may be related to its activation of SIRT1,which significantly enhances neuronal autophagy.
8.Correlation between triglyceride-glucose index and hyperuricemia in males with normal fasting blood glucose levels
Jing XUE ; Xiaowei WEI ; Suying XIA ; Weibo ZHAO ; Lintao SHI ; Jinyi SHI ; Haiying JIA ; Yueying YANG ; Xiao YANG ; Aihong WANG
Chinese Journal of Diabetes 2025;33(3):205-209
Objective To explore the correlation between triglyceride-glucose(TyG)index and hyperuricemia in men with normal fasting blood glucose(FPG)levels.Methods A total of 309 men with normal FPG who participated in a health examination at the Ninth Medical Center of the People's Liberation Army General Hospital in April 2024 were enrolled in this study.All the subjects were divided into the normal uric acid(NUA,n=218)group and the hyperuricemia(HUA,n=91)group according to serum uric acid(SUA)levels.Results Scr,TG,weight,SBP,DBP,BMI,ALT,AST,γ-GGT,and TyG index were higher in the HUA group than in the NUA group(P<0.05).Pearson and Spearman correlation analysis showed that SUA were positively correlated with Scr,eGFR,TG,weight,SBP,DBP,BMI,ALT,AST,γ-GGT and TyG(P<0.05),and negatively correlated with HDL-C(P<0.05).Logistic regression analysis showed that after adjusting for confounding factors,TyG index remained an important influencing factor for HUA.ROC curve analysis showed that the area under the ROC curve of TyG index predicting hyperuricemia in men with normal FPG was 0.665,with an cutoff value of 8.45.Conclusions TyG index in men with normal FPG are influencing factors for hyperuricemia,indicating that hyperuricemia has a close association with insulin resistance,and is an important component of metabolic syndrome.
9.Exploration of New Susceptible Genes associated with Non-Alcoholic Fatty Liver Disease among Children with Obesity Using Whole Exome Sequencing.
Xiong Feng PAN ; Cai Lian WEI ; Jia You LUO ; Jun Xia YAN ; Xiang XIAO ; Jie WANG ; Yan ZHONG ; Mi Yang LUO
Biomedical and Environmental Sciences 2025;38(6):727-739
OBJECTIVE:
This study aimed to evaluate the association between susceptibility genes and non-alcoholic fatty liver disease (NAFLD) in children with obesity.
METHODS:
We conducted a two-step case-control study. Ninety-three participants were subjected to whole-exome sequencing (exploratory set). Differential genes identified in the small sample were validated in 1,022 participants using multiplex polymerase chain reaction and high-throughput sequencing (validation set).
RESULTS:
In the exploratory set, 14 genes from the NAFLD-associated pathways were identified. In the validation set, after adjusting for sex, age, and body mass index, ECI2 rs2326408 (dominant model: OR = 1.33, 95% CI: 1.02-1.72; additive model: OR = 1.22, 95% CI: 1.01-1.47), C6orf201 rs659305 (dominant model: OR = 1.30, 95% CI: 1.01-1.69; additive model: OR = 1.21, 95% CI: 1.00-1.45), CALML5 rs10904516 (pre-ad dominant model: OR = 1.36, 95% CI: 1.01-1.83; adjusted dominant model: OR = 1.40, 95% CI: 1.03-1.91; and pre-ad additive model: OR = 1.26, 95% CI: 1.04-1.66) polymorphisms were significantly associated with NAFLD in children with obesity ( P < 0.05). Interaction analysis revealed that the gene-gene interaction model of CALML5 rs10904516, COX11 rs17209882, and SCD5 rs3733228 was optional ( P < 0.05), demonstrating a negative interaction between the three genes.
CONCLUSION
In the Chinese population, the CALML5 rs10904516, C6orf201 rs659305, and ECI2 rs2326408 variants could be genetic markers for NAFLD susceptibility.
Humans
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Non-alcoholic Fatty Liver Disease/genetics*
;
Child
;
Male
;
Female
;
Genetic Predisposition to Disease
;
Case-Control Studies
;
Exome Sequencing
;
Adolescent
;
Polymorphism, Single Nucleotide
;
Obesity/complications*
;
Pediatric Obesity/complications*
;
China

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