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.

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.

Aim To investigate the role of corylin in angiotensin Ⅱ(Ang Ⅱ)-induced cardiomyocyte hy-pertrophy and its underlying mechanisms.Methods An Ang Ⅱ-induced cardiomyocyte hypertrophy model was established and treated with corylin.Real-time PCR was employed to assess hypertrophic gene mRNA expression,and immunofluorescence was used to meas-ure cardiomyocyte surface area.Western blot and en-zyme activity assay kits were used to evaluate SIRT1 expression and activity.Results Corylin markedly mitigated Ang Ⅱ-induced hypertrophic gene expression and cardiomyocyte surface area enlargement.Moreo-ver,it prevented the Ang Ⅱ-mediated decline in SIRT1 protein levels and deacetylase activity.Further investi-gation indicated that corylin inhibited Ang Ⅱ-driven NF-κB transcriptional activity and the expression of its downstream target genes,such as TNF-α,IL-6,and IL-1β.Notably,SIRT1 silencing abolished the protective effects of corylin against cardiomyocyte hypertrophy,as well as its regulation of the SIRT1/NF-κB signaling pathway.Conclusion Corylin suppresses cardiomyo-cyte hypertrophy by modulating the SIRT1-dependent NF-κB signaling pathway.

The fat mass and obesity associated gene(FTO),a crucial RNA N6-methyladenosine(m6 A)demethylase,has been reported to influence the expression of glutathione peroxidase 4(GPX4)by modu-lating m6A modifications.GPX4 is a key molecule inhibiting ferroptosis,and the activation of ferroptosis signaling has been demonstrated to significantly reduce lipid accumulation in both mouse primary adipo-cytes and high fat diet fed mice.However,the specific m6A modification sites within the Gpx4 mRNA re-main undefined,and the regulatory role of Gpx4 during mouse adipocyte differentiation is also unclear.Through bioinformatic analysis combined with validation by methylated RNA immunoprecipitation sequen-cing(MeRIP)-qPCR and single-base elongation-and ligation-based qPCR amplification method(SE-LECT)assays,a key m6A modification site in Gpx4 mRNA was identified at 303 bp downstream from its transcription start site.CRISPR-Cas9-mediated knockdown of Gpx4 in 3T3-L1 cells,followed by adipo-genic induction,revealed that Gpx4 knockdown significantly reduced intracellular lipid droplet accumula-tion as assessed by Oil Red O staining(P＜0.001).RT-PCR and Western blotting analyses further dem-onstrated significantly decreased expression of key adipogenic differentiation genes(C/ebpα,Pparγ,Lpl,Fabp4)(P＜0.001).To investigate the temporal specificity of Gpx4 regulation,the GPX4 inhibitor RSL3(100 nmol/L)was administered during different stages of adipogenic differentiation.Results showed that RSL3 treatment specifically during the mitotic clonal expansion phase significantly suppressed the expression of adipogenic genes(Fabp4,Pparγ,Adipoq)and impeded adipogenesis.In summary,this study not only identifies a key m6A modification within the mouse Gpx4 mRNA but,more important-ly,reveals that GPX4 plays a critical regulatory role in 3T3-L1 adipocyte differentiation.These findings establish a link between the FTO-m6A-GPX4-ferroptosis regulatory axis and adipocyte differentiation,providing novel theoretical insights into the pathological mechanisms of obesity and identifying potential therapeutic targets.

Cerebral ischemic stroke(CIS)is a serious health hazard with a high disability rate.Its pathogenesis is complex and not yet fully understood,and new effective treatments need to be explored.The newly discovered pyroptosis,which is regarded as a programmed cell death mode of inflammatory response,is involved in the pathogenesis of CIS.Inhibiting cellular scorch death during CIS and reducing the inflammatory response can effectively alleviate CIS brain injury.According to traditional Chinese medicine,defi-ciency of Qi and stasis of blood are the fundamental pathogenesis of CIS.The method of benefiting Qi and activating blood is the main principle for treating CIS.Therefore,in this paper,we link cell pyroptosis with Qi deficiency and blood stasis,review the progress of research on reducing brain tissue damage in CIS by inhibiting pyroptosis through the method of benefiting Qi and invigorating blood.

Objective:An in vivo mammalian hepatocyte Unscheduled DNA Synthesis(UDS)test was used to evaluate the genotoxicity of Cross-linked Sodium Hyaluronate Gel and Bone Repair Materials,providing experimental evidence for establishing a UDS testing method for medical devices and materials.Methods:0.9％sodium chloride injection and cottonseed oil were used as the solvent for test materials and negative control,respectively.N-dimethylnitrosamine(NDMA)was used as the positive control for the early sampling times,and 2-acetylaminofluorene(2-AAF)was used as the positive control for the late sampling times.SD rats were administered a single dose for toxic exposure,and liver tissues were collected at 4 h and 16 h,respectively.Hepatocytes were isolated using collagenase perfusion.After labeling with 5-ethynyl-2'-deoxyuridine(EdU),and the net average fluorescence intensity(NAFI)of cell nuclei and nucleoplasm was measured by fluorescence microscope.Data from 50 cells were used to analyze the DNA repair level.Results:Compared with the negative control groups,the positive control groups(NDMA and 2-AAF)showed highly statistically significant differences in NAFI(P＜0.01),indicating successful induction of DNA damage.There was no statistically significant differences between the cross-linked sodium hyaluronate gel groups,bone repair material groups and the negative control group(P＞0.05),suggesting that these materials did not significantly induce DNA damage under the experimental conditions.Conclusion:This study first applied EdU labeling technology to the in vivo hepatic UDS assay,achieving non-radioactive labeling through click chemistry reactions.Under the conditions of this study,cross-linked sodium hyaluronate gel and bone repair materials did not exhibit genotoxicity.In the follow-up,the sample range can be expanded and the observation period can be prolonged to further improve the genotoxicity evaluation system of medical devices.

Objective:An in vivo mammalian hepatocyte Unscheduled DNA Synthesis(UDS)test was used to evaluate the genotoxicity of Cross-linked Sodium Hyaluronate Gel and Bone Repair Materials,providing experimental evidence for establishing a UDS testing method for medical devices and materials.Methods:0.9％sodium chloride injection and cottonseed oil were used as the solvent for test materials and negative control,respectively.N-dimethylnitrosamine(NDMA)was used as the positive control for the early sampling times,and 2-acetylaminofluorene(2-AAF)was used as the positive control for the late sampling times.SD rats were administered a single dose for toxic exposure,and liver tissues were collected at 4 h and 16 h,respectively.Hepatocytes were isolated using collagenase perfusion.After labeling with 5-ethynyl-2'-deoxyuridine(EdU),and the net average fluorescence intensity(NAFI)of cell nuclei and nucleoplasm was measured by fluorescence microscope.Data from 50 cells were used to analyze the DNA repair level.Results:Compared with the negative control groups,the positive control groups(NDMA and 2-AAF)showed highly statistically significant differences in NAFI(P＜0.01),indicating successful induction of DNA damage.There was no statistically significant differences between the cross-linked sodium hyaluronate gel groups,bone repair material groups and the negative control group(P＞0.05),suggesting that these materials did not significantly induce DNA damage under the experimental conditions.Conclusion:This study first applied EdU labeling technology to the in vivo hepatic UDS assay,achieving non-radioactive labeling through click chemistry reactions.Under the conditions of this study,cross-linked sodium hyaluronate gel and bone repair materials did not exhibit genotoxicity.In the follow-up,the sample range can be expanded and the observation period can be prolonged to further improve the genotoxicity evaluation system of medical devices.

Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans ; Root Canal Therapy/adverse effects* ; Consensus ; Root Canal Preparation/adverse effects*

Objective:To investigate the clinical characteristics of patients with high-myopia macular hole retinal detachment (MHRD) combined with choroidal detachment and to preliminarily analyze factors associated with postoperative hole closure.Methods:A retrospective clinical case series study. A total of 68 patients with high myopia (68 eyes) with MHRD diagnosed by Department of Ophthalmology, Peking University People’s Hospital from January 2019 to April 2024 were included in this study. Among them, there were 14 males (14 eyes) and 54 females (54 eyes). The mean age was (61.10±9.66) years. All eyes were treated with pars plana vitrectomy (PPV) combined with silicone oil or gas filling. Best corrected visual acuity (BCVA), intraocular pressure, and B-mode ultrasonography were performed. The BCVA test was performed using the Snellen visual acuity chart, which was statistically converted to logarithm of the minimum angle of resolution (logMAR) visual acuity. The range of choroidal detachment was defined according to the number of involved quadrants observed in B-mode ultrasound or surgery, which was divided into 1 to 4 quadrants. Axial length (AL) was measured under retinal reattachment. In 68 eyes, there were 17 eyes with choroidal detachment and 51 eyes without choroidal detachment, respectively. There were 17 eyes with choroidal detachment, and the detachment range involved 1, 2, 2 and 12 eyes in 1, 2, 3 and 4 quadrants, respectively. During operation, 13% C 3F 8 was filled in 2 eyes, all of which were not complicated with choroidal detachment. 66 eyes were filled with silicone oil. According to whether the patients were complicated with choroidal detachment, the patients were divided into the group without choroidal detachment and the group with choroidal detachment. Independent sample t test, Welch two-sample t test or Mann-Whitney U test were used for comparison between groups. Generalized linear regression and logistic regression were used to analyze the relationship between the aperture size of postoperative unclosed holes and the closed hole after surgery and clinical factors. Results:At 3 months after surgery, the logMAR BCVA of the affected eye was 1.29±0.43, with a preoperative to postoperative difference ranging from -1.60 to 0.70 (-0.51±0.51) logMAR units. The AL ranged from 26.6 to 34.3 (29.60±2.12) mm. Among 68 eyes, macular hole of 37 (54.4%, 37/68) eyes were open and 31 (45.6%, 31/68) eyes were closed, respectively. The hole diameter of the open eye was (753±424) μm. There was no significant difference in age, course of disease and AL between the two groups ( W=412.0, 477.5, 427.0; P>0.05). Before operation, BCVA in patients with choroidal detachment was worse ( W=257.5) and intraocular pressure was lower ( t=4.051) in patients with choroidal detachment compared with those without choroidal detachment, with statistical significance ( P<0.05). At 3 months after surgery, BCVA in patients with choroidal detachment was significantly worse than that in patients without choroidal detachment, with statistical significance ( W=284.0, P<0.05). There were no significant differences in logMAR BCVA difference ( t=0.616) and macular hole closure rate ( χ 2=0.000) before and after surgery ( P>0.05). The reoperation rate of retinal detachment due to persistent or recurrent retinal detachment was significantly higher in the group with choroid detachment than in the group without choroid detachment, and the difference was statistically significant (odds ratio=6.424, P<0.05). Logistic regression analysis showed that young age was significantly correlated with macular hole closure failure after surgery ( β=0.077, P=0.015). There was no correlation between AL, duration of disease, BCVA before surgery, intraocular pressure, wether combined with choroid detachment range and postoperative hole closure ( β=-0.072, 0.000, 0.672, -0.085, -0.391; P>0.05). Conclusions:Concomitant choroidal detachment adversely affected on both pre-operative and post-operative visual acuity in high myopia MHRD. It is closely associated with the risk of recurrent retinal detachment and the needs of multiple operations, but has no significant effect on hole closure rate. Lower age of onset may be a risk factor for macular hole closure.

Objective:To establish 30-day of age transcutaneous bilirubin (TcB) reference curves for healthy neonates, and to investigate regional variations in bilirubin dynamics.Methods:A multicenter retrospective cohort study was conducted. A total of 220 950 healthy neonates born at a gestational age of 35-<42 weeks, with a birth weight ≥2 000 g, who did not receive phototherapy within 60 h after birth were recruited. All of them underwent remote TcB monitoring using the Bilibaby remote jaundice monitoring system between August 1 st, 2020 and December 31 st, 2024 in 426 hospitals. TcB data were collected within the period from birth to 30-day of age. The P40, P75, and P95 of TcB values were calculated, and dynamic TcB curves for 30-day of age were constructed. Patterns of bilirubin change, rates of change, and transition outcomes were described. Regional comparisons between South and North were conducted using linear mixed-effects models for TcB trajectories and Pearson′s chi-square test for outcome differences. Results:A total of 220 950 neonates were included, of whom 101 711 (46.03%) were female. Gestational age at birth was (38.75±1.12) weeks, and birth weight was (3 272±417) g. TcB levels increased rapidly within 3-day of age, peaked at 4-6-day of age, with peak values at P40, P75, and P95 of 200.6, 239.7 and 275.4 μmol/L (11.8, 14.1 and 16.2 mg/dl), respectively. TcB levels gradually declined thereafter and stabilized after 13-day of age, with values at P40, P75, and P95 fluctuating between 147.9-159.8, 190.4-200.6, and 231.2-239.7 μmol/L (8.7-9.4, 11.2-11.8, 13.6-14.1 mg/dl), respectively. Notably, among neonates categorized as low-or low-intermediate-risk within 3-day of age, 6 700 (12.76%) progressed to intermediate-high or high risk between 4 and 30 days of age. Before 13-day of age, TcB levels in the southern regions were consistently higher than those in the northern regions ( P=0.039); from 14 to 30 days of age, the overall TcB levels had no statistically difference, but the temporal changes in TcB still showed regional differences (degrees of freedom=3, all interaction P<0.05). Among neonates classified as low-or low-intermediate risk within 3-day of age, 25 326 were from southern regions, of whom 4 254 (16.80%) progressed to intermediate-high or high risk between 4 and 30 days of age. In northern regions, 27 193 neonates were classified as low-or low-intermediate risk within 3-day of age, among whom 2 446 (8.99%) progressed to intermediate-high or high risk. The risk progression between the 2 regions had statistically difference ( χ2=716.49, P<0.001). Conclusions:A TcB percentile curve for neonates within 30-day of age was established, revealing that both the overall TcB level and its temporal trend were higher in southern than in northern newborns. These findings provide baseline data to support continuous management of neonatal jaundice.