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.

Objective: To conduct screening for rare blood types within important blood group systems for the Chinese population, such as Rh, Duffy, Kidd, P1Pk, Diego, and MNS, in the Guangzhou region, and to establish a corresponding rare blood type database and physical repository. Methods: The saline medium microplate method was used to screen blood donors with the ccDEE phenotype combined with either Jk(a-) or Jk(b-). The polybrene microplate method was employed to screen for donors with Fy(a-), s(-), Lu(b-), Di(b-), k(-), and p phenotypes. The urea lysis microplate method was applied to screen for the Jk(a-b-) phenotype. A high-resolution melting (HRM) curve method was established for screening some donors with the Di(b-) phenotype. Subsequently, expanded phenotyping of antigens in the Rh, Kidd, MNS, Duffy, P1Pk, Lewis, Kell, and Lutheran blood group systems was performed on identified rare blood type donors using monoclonal antibodies. The test results are entered into the Rare Blood Type Bank Management System of the Guangzhou Blood Center, enabling functions such as confirmation reminders and cryopreservation storage when the donor donates again. Red blood cells of rare blood types are processed into frozen red blood cells for long-term storage. Results: Among voluntary blood donors, 16 cases of the ccDEE combined with Jk(a-) phenotype were identified (0.221 7%, 16/7 216); 10 cases of the ccDEE combined with Jk(b-) phenotype (0.138 6%, 10/7 216); 78 cases of the Fy(a-) phenotype (0.169 5%, 78/46 012); 39 cases of the Lu(b-) phenotype (0.138 2%, 39/28 214); 31 cases of the s(-) phenotype (0.081 8%, 31/37 913); 22 cases of the Di(b-) phenotype (0.029 9%, 22/73 691); 30 cases of the Jk(a-b-) phenotype (0.010 1%, 30/298 250); and 1 case of the k(-) phenotype (0.001 3%, 1/77 382), which was further identified as KELnull phenotype (K0). No p phenotype donors were identified (0/88 528). A total of 228 units of frozen red blood cells were prepared. The screening results were compared and analyzed with rare blood type data from other regions. Conclusion: This study, through a combination of different screening methods, significantly improved the efficiency of rare blood type screening while remaining cost-effective. By conducting large-scale screening and performing data informatization processing, a database and physical repository of rare blood types in the Guangzhou region were successfully established. This provides a strong guarantee for the timely supply of blood to patients with difficult-to-match and rare blood types in the region, effectively enhances the level of transfusion safety in the region, and offers a practical paradigm for constructing a comprehensive blood transfusion support system.

Objective:To analyze the revision strategies for failed atlantoaxial dislocation (AAD) surgery.Methods:A retrospective analysis was conducted on 145 patients who underwent revision surgery for AAD at the General Hospital of Southern Theatre Command of PLA between September 2009 and December 2023. The cohort included 74 males and 71 females, with a mean age of 43±16 years (range, 6-72 years). The initial surgical approaches were: anterior 31 cases, posterior 114 cases. Based on imaging assessments of immediate postoperative reduction and fusion status prior to revision, the cases of failure were classified into reduction-nonfusion type (22 cases), nonreduction-fusion type (31 cases), and nonreduction-nonfusion type (92 cases). Among the nonreduction-nonfusion cases, 39 had initial surgery with internal fixation for reduction, while 53 had initial surgery with simple decompression (posterior arch resection, foramen magnum decompression) without reduction. In the nonreduction-fusion cases, 8 cases had spot fusion and 23 had extensive fusion. Japanese Orthopaedic Association (JOA) scores were compared before and after revision, and complication rates were observed.Results:All patients successfully underwent surgery. The revision approaches included: anterior (anterior fixation and fusion 52 cases, anterior implant removal combined anterior fixation and fusion 4 cases, transoral odontoidectomies 16 cases, anterior implant removal combined transoral odontoidectomy 2 cases), posterior (posterior fixation and fusion 2 cases, posterior implant removal combined posterior fixation and fusion 22 cases), and combined anterior-posterior (posterior implant removal combined anterior fixation and fusion 18 cases, anterior implant removal combined posterior fixation and fusion 25 cases, posterior implant removal combined transoral odontoidectomy 5 cases). Operative time was 254.20±107.63 min (range, 90-660 min), and blood loss was 218.83±172.17 ml (range, 20-800 ml). Except for 3 patients who died due to postoperative complications, all patients were followed up for a duration of 12±11 months (range, 3-60 months). Six patients who failed to achieve bony fusion after the initial revision surgery underwent a second revision due to poor reduction (1 case), infection (1 case), suboptimal implant position (3 cases), and graft nonunion (1 case). All three patients with bony fusion after the initial revision surgery underwent a second revision due to poor reduction. Following the second revision surgery, none of the 9 patients exhibited graft nonunion or spinal cord compression. The 136 successful initial revision cases had a final follow-up JOA score of 14.75±2.00, significantly higher than the preoperative score of 11.93±2.92 ( t=-18.869, P<0.001). Conclusions:Revision surgery for AAD should take into account the immediate postoperative reduction status and fusion status prior to revision. An appropriate revision strategy should be selected to achieve satisfactory reduction and bony fusion.

Objective To develop the Ego Depletion Scale for Type 2 Diabetes Patients and evaluate its reliability and validity,and to provide a specific assessment tool for evaluating ego-depletion in self-management.Methods Guided by the self-control strength model,the initial scale was constructed through literature review,semi-structured interviews,2 rounds of expert consultation,and a pilot survey.A convenience sampling method was employed to recruit 460 patients with Type 2 Diabetes from the endocrinology department of a tertiary hospital in Wuhan,Hubei Province,between April and July 2024.They were randomly divided into 2 subsets for exploratory factor analysis and confirmatory factor analysis.Results A total of 451 valid questionnaires were collected.Exploratory factor analysis extracted 6 common factors,with a cumulative variance contribution of 73.231％.In confirmatory factor analysis,an item was deleted due to failing to meet the standardized loading value criterion.The revised Ego Depletion Scale for Type 2 Diabetes Patients comprised 6 dimensions and 22 items.The total Cronbach's α coefficient was 0.911;split-half reliability was 0.744;the content validity index was 0.860.Correlation coefficients between the total score and scores of each dimension of the scale and the total score of the Self-Regulatory Fatigue Scale ranged from 0.558 to 0.946(P＜0.001).Conclusion The scale exhibits robust reliability and validity,serving as a scientifically instrument for assessing ego depletion in patients with Type 2 Diabetes.

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.

OBJECTIVES: To explore the risk factors of feeding intolerance (FI) in critically ill children receiving enteral nutrition (EN) and to construct a prediction nomogram model for FI. METHODS: A retrospective study was conducted to collect data from critically ill children admitted to the Pediatric Intensive Care Unit of Xiangya Hospital, Central South University, between January 2015 and October 2020. The children were randomly divided into a training set (346 cases) and a validation set (147 cases). The training set was further divided into a tolerance group (216 cases) and an intolerance group (130 cases). Multivariate logistic regression analysis was used to screen for risk factors for FI in critically ill children receiving EN. A nomogram was constructed using R language, which was then validated on the validation set. The model's discrimination, calibration, and clinical net benefit were evaluated using receiver operating characteristic curves, calibration curves, and decision curves. RESULTS: Duration of bed rest, shock, gastrointestinal decompression, use of non-steroidal anti-inflammatory drugs, and combined parenteral nutrition were identified as independent risk factors for FI in critically ill children receiving EN (P<0.05). Based on these factors, a nomogram prediction model for FI in critically ill children receiving EN was developed. The area under the receiver operating characteristic curve for the training set and validation set was 0.934 (95%CI: 0.906-0.963) and 0.852 (95%CI: 0.787-0.917), respectively, indicating good discrimination of the model. The Hosmer-Lemeshow goodness-of-fit test showed that the model had a good fit (χ 2=12.559, P=0.128). Calibration curve and decision curve analyses suggested that the model has high predictive efficacy and clinical application value. CONCLUSIONS Duration of bed rest, shock, gastrointestinal decompression, use of non-steroidal anti-inflammatory drugs, and combined parenteral nutrition are independent risk factors for FI in critically ill children receiving EN. The nomogram model developed based on these factors exhibits high predictive efficacy and clinical application value.
Humans ; Critical Illness ; Enteral Nutrition/adverse effects* ; Male ; Risk Factors ; Female ; Child, Preschool ; Infant ; Nomograms ; Retrospective Studies ; Child ; Logistic Models

OBJECTIVES: To investigate the application value of targeted next-generation sequencing (tNGS) in the etiological diagnosis of moderate to severe respiratory distress syndrome (RDS) in neonates. METHODS: A prospective randomized controlled trial was conducted, enrolling 81 term and late-preterm neonates with moderate to severe RDS admitted to Fujian Children's Hospital between December 2023 and December 2024. Patients were randomly assigned to the conventional microbiological test (CMT) group (n=42) or the tNGS group (n=39). For routine pathogen detection, bronchoalveolar lavage fluid was obtained via bronchoscopy, and lower respiratory tract specimens were collected via the endotracheal tube; all specimens underwent culture, and some specimens additionally underwent polymerase chain reaction or antigen testing. In the tNGS group, tNGS was performed in addition to routine pathogen detection on the same specimen types. The detection rate of pathogens, the detection rate of co-infections, and the duration of antibiotic use were compared between the two groups. RESULTS: The pathogen detection rate in the tNGS group (18/39, 46%) was significantly higher than that in the CMT group (8/42, 19%) (P=0.009). The co-infection detection rate was 13% (5/39) in the tNGS group, while no co-infections were identified in the CMT group (P=0.024). Regarding treatment, the duration of antibiotic use in the tNGS group was shorter than that in the CMT group [(12±4) days vs (15±5) days, P=0.003]. CONCLUSIONS tNGS significantly improves the pathogen detection rate in neonates with moderate to severe RDS and offers advantages in the rapid identification of co-infections and reduction of antibiotic treatment duration, suggesting it has clinical utility and potential for wider adoption.
Humans ; Prospective Studies ; Infant, Newborn ; Female ; Respiratory Distress Syndrome, Newborn/etiology* ; Male ; High-Throughput Nucleotide Sequencing/methods*

OBJECTIVES: To evaluate the safety and efficacy of thiotepa (TT)-containing conditioning regimens for allogeneic hematopoietic stem cell transplantation (HSCT) in children with inborn errors of immunity (IEI). METHODS: Clinical data of 22 children with IEI who underwent HSCT were retrospectively reviewed. Survival after HSCT was estimated using the Kaplan-Meier method. RESULTS: Nine patients received a traditional conditioning regimen (fludarabine + busulfan + cyclophosphamide/etoposide) and underwent peripheral blood stem cell transplantation (PBSCT). Thirteen patients received a TT-containing modified conditioning regimen (TT + fludarabine + busulfan + cyclophosphamide), including seven PBSCT and six umbilical cord blood transplantation (UCBT) cases. Successful engraftment with complete donor chimerism was achieved in all patients. Acute graft-versus-host disease occurred in 12 patients (one with grade III and the remaining with grade I-II). Chronic graft-versus-host disease occurred in one patient. The incidence of EB viremia in UCBT patients was lower than that in PBSCT patients (P<0.05). Over a median follow-up of 36.0 months, one death occurred. The 3-year overall survival (OS) rate was 100% for the modified regimen and 88.9% ± 10.5% for the traditional regimen (P=0.229). When comparing transplantation types, the 3-year OS rates were 100% for UCBT and 93.8% ± 6.1% for PBSCT (P>0.05), and the 3-year event-free survival rates were 100% and 87.1% ± 8.6%, respectively (P>0.05). CONCLUSIONS TT-containing conditioning for allogeneic HSCT in children with IEI is safe and effective. Both UCBT and PBSCT may achieve high success rates.
Humans ; Retrospective Studies ; Transplantation Conditioning/methods* ; Thiotepa/therapeutic use* ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Male ; Female ; Child, Preschool ; Infant ; Child ; Transplantation, Homologous ; Graft vs Host Disease ; Adolescent

OBJECTIVE: To explore the effect and mechanism of DNA methyltransferase 1 (DNMT1) knockout on the inhibition of acute myeloid leukemia (AML) by natural killer (NK) cells. METHODS: The peripheral blood NK cells of AML patients and controls were collected, and the mRNA and protein level of DNMT1 were measured by PCR and Western blot, respectively. The DNMT1 knockout mice were constructed to obtain NK^DNMT1-/- cells. The NK cells were stimulated with interleukin (IL)-12, IL-15, and IL-18 to construct memory NK cells, and then the interferon-γ (IFN-γ) levels were measured by ELISA. After co-culturing with memory NK cells and HL60 cells, the killing effect of NK^DNMT1-/- cells on HL60 cells was detected by LDH assay. Then, the HL60 cell apoptosis and NK cell NKG2D level were measured by flow cytometry. The perforin and granzyme B protein levels of NK cells were measured by Western blot. The AML model mice were constructed by injecting HL60 cells into the tail vein, meanwhile, memory NK cells were also injected, and then the mouse weights, CD33 positive rates, and survival time were detected. RESULTS: The mRNA and protein levels of DNMT1 in NK cells of AML patients were significantly higher than those in the control group (both P < 0.01), while the IFN-γ level induced by interleukin was significantly lower than that in the control group (P < 0.05). Compared with NK^DNMT1+/+ cells, the ability of NK^DNMT1-/- cells to secrete IFN-γ after interleukin stimulation was significantly increased (P < 0.05). The killing and apoptosis-inducing effects of NK^DNMT1-/- cells on HL60 cells were significantly stronger than those of NK^DNMT1+/+ cells (both P < 0.05). The NKG2D level and expression of perforin and granzyme B of NK^DNMT1-/- cells were significantly increased compared with NK^DNMT1+/+ cells (all P < 0.05). Compared with AML mice injected with NK^DNMT1+/+ cells, AML mice injected with NK^DNMT1-/- cells showed significantly increased body weight, decreased CD33 positive rate, and prolonged survival time (all P < 0.05). CONCLUSION Knocking out DNMT1 can enhance the inhibitory effect of NK cells on AML, which may be related to enhancing NK cell memory function.
Killer Cells, Natural/metabolism* ; Animals ; Leukemia, Myeloid, Acute ; Humans ; DNA (Cytosine-5-)-Methyltransferase 1 ; Mice ; Mice, Knockout ; HL-60 Cells ; Apoptosis ; Interferon-gamma/metabolism* ; Granzymes/metabolism* ; Perforin/metabolism* ; NK Cell Lectin-Like Receptor Subfamily K/metabolism*