Objective To evaluate the safety and efficacy of a self-developed micro-normothermic machine perfusion (NMP) system (micro-perfusion device) for preserving isolated porcine limbs. Methods Five healthy Landrace pigs were selected, and their left and right forelimbs were randomly divided into the NMP group and static cold storage (SCS) group. The NMP group was perfused with the self-developed micro-perfusion device and polymerized hemoglobin perfusate for 32 hours at normothermia, while the SCS group was preserved at 4 ℃. Hemodynamic parameters such as perfusion pressure and flow were monitored. The pH value, partial pressure of oxygen (PO₂), lactic acid (Lac), creatine kinase (CK) and lactate dehydrogenase (LDH) in the perfusate were measured. Hematoxylin-eosin staining was used to assess the muscle tissue structure, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling was employed to evaluate muscle cell apoptosis, and immunohistochemistry staining was applied to detect the expressions of tumor necrosis factor (TNF)-α and interleukin (IL)-6. A mixed-effects model was used to analyze the effects of time and treatment methods on tissue structure, cell apoptosis and inflammatory factors. Results The device could stably maintain a perfusion pressure of (69±15) mmHg and a flow rate of (117±42) mL/min. The pH value and electrolytes of the perfusate were generally stable, with PO₂ maintained at a high level. Lac was maintained at 5.38(3.81, 6.45) mmol/L, while CK and LDH increased over time. After 32 hours of perfusion in the NMP group, both the myocyte spacing and apoptosis rate were better than those in the SCS group. Mixed-effects model analysis showed that there were statistically significant differences in the effects of NMP treatment and SCS treatment on myocyte spacing and apoptosis rate per unit time (both P < 0.05). There were no statistically significant differences in TNF-α and IL-6 between the two groups, and mixed-effects model analysis showed no statistically significant differences in the effects of NMP treatment and SCS treatment on TNF-α and IL-6 per unit time (both P > 0.05). Conclusions The micro-perfusion device used in this study may achieve 32-hour normothermic preservation in a porcine limb amputation model, maintain basic metabolism and ionic homeostasis, reduce muscle structural damage and cell apoptosis without inducing additional inflammatory responses. This technology is expected to significantly extend the time window for replantation of amputated limbs in disaster rescue and long-distance transportation, providing an important technical basis for clinical translation and subsequent replantation research.

Purpose: Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative. Methods: As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers. Results: The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting. Conclusion This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.

Objective:To explore the impact of the two-way referral model on compliance and prognosis in patients with heart failure.Methods:This bidirectional cohort study enrolled chronic heart failure (CHF) patients treated at Qilu Hospital of Shandong University or designated primary hospitals between March 2018 and March 2022. Patients were categorized into two groups based on referral status: two-way referral group (participating in the referral model with≥1 follow-up visit at primary hospitals) and the core hospital group (receiving treatment and follow-up exclusively at Qilu Hospital). Baseline clinical characteristics were collected and compared between groups. Patients underwent followed-up, with primary endpoints including follow-up rate, drug (β-blockers, angiotension converting enzyme inhibitor (ACEI)/angiotensin Ⅱ receptor blockers (ARB)/angiotensin receptor-neprilysin inhibitor (ARNI), sodium-glucose cotransporter 2 inhibitors and mineralocorticoid receptor antagonists) utilization rate and target dose achievement rate. Secondary endpoints encompassed changes from baseline in left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDd), and N-terminal pro-brain natriuretic peptide (NT-proBNP), plus cardiovascular mortality and heart failure rehospitalization. Generalized linear mixed models analyzed longitudinal trends in LVEF, LVEDd, and NT-proBNP levels. Kaplan-Meier curves and Cox regression evaluated LVEF recovery rates, supplemented by subgroup analyses. Multivariate logistic regression was used to identify factors influencing target dose achievement rate for β-blockers and ACEI/ARB/ARNI therapies in CHF patients.Results:A total of 357 patients were enrolled, aged 53 (41, 63) years, including 256 males (71.7%). 157 patients were in the two-way referral group and 200 patients in the core hospital-treated group. Compared with the core hospital-treated group, the two-way referral group had lower baseline LVEF (28 (22, 34)% vs. 31 (23, 36)%, P=0.021) and systolic blood pressure (116 (104, 125) mmHg vs. 121 (109, 134) mmHg (1 mmHg=0.133 kPa), P=0.010). The 12-month follow-up rate of the two-way referral group was higher than the core hospital-treated group (73.8% vs. 56.0%, P=0.004). No significant between-group differences were observed in drug utilization rate of β-blockers, ACEI/ARB/ARNI, or sodium-glucose cotransporter 2 inhibitors during follow-up (all P>0.05), while mineralocorticoid receptor antagonists use showed a declining trend in both groups. Although the core hospital-treated group had higher target dose achievement rates for β-blockers (65.4% vs. 49.3%, P=0.042) and ACEI/ARB/ARNI (79.8% vs. 65.8%, P=0.046) than the two-way referral group, multivariate logistic regression indicated that the two-way referral model was not a negative predictor for these outcomes (all P>0.05). Both groups showed improved NT-proBNP, LVEDd, and LVEF from baseline (all P<0.001) with no significant difference in trends between groups (all P>0.05). There was no significant difference in the composite incidence (7.6% vs. 6.5%, P=0.674) and cumulative incidence (log-rank P=0.684) of cardiovascular death and heart failure rehospitalization at 12 months between two groups. Conclusion:The two-way referral model demonstrates advantages in improving medication adherence, drug utilization rates, and targetdoseachievement rates among CHF patients. This model not only promotes cardiac functional recovery but also reduces risks of cardiovascular mortality and heart failure rehospitalization, achieving comparable therapeutic and management outcomes to those observed in core hospital-treated patients.

Objective To explore the protective effects of genetically modified porcine erythrocyte suspension as a subnormothermic normoxic mechanical perfusate on hypoxic-ischemic brain injury in cynomolgus monkeys caused by traumatic hemorrhage.Methods Cynomolgus monkeys were randomly divided into positive and negative control groups(a total of 3 monkeys,with 3 left cerebral hemispheres as the positive control group and 3 right cerebral hemispheres as the negative control group)and the subnormothermic perfusion group(n=3).The positive control group was directly sampled 1 hour after circulatory arrest,while the negative control group was placed at subnormothermic conditions for 6 hours after circulatory arrest.The subnormothermic perfusion group underwent 6 hours of subnormothermic normoxic mechanical perfusion of the bilateral common carotid arteries of the cynomolgus monkey hypoxic-ischemic brain injury model using genetically modified porcine erythrocyte suspension 1 hour after circulatory arrest.Before perfusion,cross-matching experiments were conducted between the six genetically modified pig and the cynomolgus monkeys.After the start of perfusion,the levels of routine blood indicators in the perfusate were detected at 0,1,2,3,4,5 and 6 hours.Blood oxygen saturation was recorded,and the levels of Na+,K+,Ca2+,glucose and blood pH in the perfusate were measured,as well as the levels of IgG and IgM in the perfusate.After 6 hours of perfusion,the water content of the brain tissue was measured.Nissl staining was performed on the frontal cortex and hippocampal regions,and immunofluorescence staining was used to detect the expression of glial fibrillary acidic protein(GFAP),ionized calcium-binding adapter molecule 1(Iba1)and neuronal nuclear antigen(NEUN).Results The cross-matching results between the six genetically modified pig and the cynomolgus monkeys were negative.The number of red blood cells in the perfusate decreased significantly at 3 hours of perfusion,and the hemoglobin level showed a downward trend at 1,3,5 and 6 hours.The number of white blood cells and platelets decreased at all time points.The blood oxygen saturation in the subnormothermic perfusion group remained stable at 95%-98%,and the levels of blood oxygen saturation,Na+,Ca2+,glucose and pH were stable,while the K+level first increased and then decreased.There was no significant difference in the levels of IgG and IgM before and after perfusion.The water content of brain tissue at the end of perfusion in the subnormothermic perfusion group was significantly higher than that in the positive control group(P<0.001).Nissl staining results showed that compared with the positive control group,the pyramidal neurons in the prefrontal cortex of the subnormothermic perfusion group maintained better morphological integrity,with no significant increase in enlarged and deformed cells.In the hippocampal CA1 region,there was a slight increase in enlarged and deformed cells,and a few cells with undamaged structures showed reduced cell size.In the hippocampal dentate gyrus,fewer granule neurons had compromised structural integrity,with increased cell edema.NEUN immunofluorescence staining showed that compared with the positive control group,the pyramidal neurons in the prefrontal cortex and hippocampal CA1 region of the subnormothermic perfusion group had better morphological states,with clear axons.The granule cells in the hippocampal dentate gyrus were well preserved,but the nuclei were less well protected.GFAP immunofluorescence staining showed that compared with the positive control group,the subnormothermic perfusion group had sparser protrusions that were more tightly associated with neurons.Iba1 immunofluorescence staining showed that compared with the positive control group,the subnormothermic perfusion group had thicker and fewer protrusions.Conclusions Compared with the positive control group,subnormothermic normoxic mechanical perfusion with genetically modified porcine erythrocyte perfusate increases brain tissue edema in cynomolgus monkeys,but better preserves the morphological integrity of neurons and glial cells.The protective effects may be related to the continuous oxygen and energy supply,maintenance of ion homeostasis and perfusate pH,reduced rejection,and low metabolic state of the whole brain.

Objective To explore the protective effects of genetically modified porcine erythrocyte suspension as a subnormothermic normoxic mechanical perfusate on hypoxic-ischemic brain injury in cynomolgus monkeys caused by traumatic hemorrhage.Methods Cynomolgus monkeys were randomly divided into positive and negative control groups(a total of 3 monkeys,with 3 left cerebral hemispheres as the positive control group and 3 right cerebral hemispheres as the negative control group)and the subnormothermic perfusion group(n=3).The positive control group was directly sampled 1 hour after circulatory arrest,while the negative control group was placed at subnormothermic conditions for 6 hours after circulatory arrest.The subnormothermic perfusion group underwent 6 hours of subnormothermic normoxic mechanical perfusion of the bilateral common carotid arteries of the cynomolgus monkey hypoxic-ischemic brain injury model using genetically modified porcine erythrocyte suspension 1 hour after circulatory arrest.Before perfusion,cross-matching experiments were conducted between the six genetically modified pig and the cynomolgus monkeys.After the start of perfusion,the levels of routine blood indicators in the perfusate were detected at 0,1,2,3,4,5 and 6 hours.Blood oxygen saturation was recorded,and the levels of Na+,K+,Ca2+,glucose and blood pH in the perfusate were measured,as well as the levels of IgG and IgM in the perfusate.After 6 hours of perfusion,the water content of the brain tissue was measured.Nissl staining was performed on the frontal cortex and hippocampal regions,and immunofluorescence staining was used to detect the expression of glial fibrillary acidic protein(GFAP),ionized calcium-binding adapter molecule 1(Iba1)and neuronal nuclear antigen(NEUN).Results The cross-matching results between the six genetically modified pig and the cynomolgus monkeys were negative.The number of red blood cells in the perfusate decreased significantly at 3 hours of perfusion,and the hemoglobin level showed a downward trend at 1,3,5 and 6 hours.The number of white blood cells and platelets decreased at all time points.The blood oxygen saturation in the subnormothermic perfusion group remained stable at 95%-98%,and the levels of blood oxygen saturation,Na+,Ca2+,glucose and pH were stable,while the K+level first increased and then decreased.There was no significant difference in the levels of IgG and IgM before and after perfusion.The water content of brain tissue at the end of perfusion in the subnormothermic perfusion group was significantly higher than that in the positive control group(P<0.001).Nissl staining results showed that compared with the positive control group,the pyramidal neurons in the prefrontal cortex of the subnormothermic perfusion group maintained better morphological integrity,with no significant increase in enlarged and deformed cells.In the hippocampal CA1 region,there was a slight increase in enlarged and deformed cells,and a few cells with undamaged structures showed reduced cell size.In the hippocampal dentate gyrus,fewer granule neurons had compromised structural integrity,with increased cell edema.NEUN immunofluorescence staining showed that compared with the positive control group,the pyramidal neurons in the prefrontal cortex and hippocampal CA1 region of the subnormothermic perfusion group had better morphological states,with clear axons.The granule cells in the hippocampal dentate gyrus were well preserved,but the nuclei were less well protected.GFAP immunofluorescence staining showed that compared with the positive control group,the subnormothermic perfusion group had sparser protrusions that were more tightly associated with neurons.Iba1 immunofluorescence staining showed that compared with the positive control group,the subnormothermic perfusion group had thicker and fewer protrusions.Conclusions Compared with the positive control group,subnormothermic normoxic mechanical perfusion with genetically modified porcine erythrocyte perfusate increases brain tissue edema in cynomolgus monkeys,but better preserves the morphological integrity of neurons and glial cells.The protective effects may be related to the continuous oxygen and energy supply,maintenance of ion homeostasis and perfusate pH,reduced rejection,and low metabolic state of the whole brain.

Objective:To explore the impact of the two-way referral model on compliance and prognosis in patients with heart failure.Methods:This bidirectional cohort study enrolled chronic heart failure (CHF) patients treated at Qilu Hospital of Shandong University or designated primary hospitals between March 2018 and March 2022. Patients were categorized into two groups based on referral status: two-way referral group (participating in the referral model with≥1 follow-up visit at primary hospitals) and the core hospital group (receiving treatment and follow-up exclusively at Qilu Hospital). Baseline clinical characteristics were collected and compared between groups. Patients underwent followed-up, with primary endpoints including follow-up rate, drug (β-blockers, angiotension converting enzyme inhibitor (ACEI)/angiotensin Ⅱ receptor blockers (ARB)/angiotensin receptor-neprilysin inhibitor (ARNI), sodium-glucose cotransporter 2 inhibitors and mineralocorticoid receptor antagonists) utilization rate and target dose achievement rate. Secondary endpoints encompassed changes from baseline in left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDd), and N-terminal pro-brain natriuretic peptide (NT-proBNP), plus cardiovascular mortality and heart failure rehospitalization. Generalized linear mixed models analyzed longitudinal trends in LVEF, LVEDd, and NT-proBNP levels. Kaplan-Meier curves and Cox regression evaluated LVEF recovery rates, supplemented by subgroup analyses. Multivariate logistic regression was used to identify factors influencing target dose achievement rate for β-blockers and ACEI/ARB/ARNI therapies in CHF patients.Results:A total of 357 patients were enrolled, aged 53 (41, 63) years, including 256 males (71.7%). 157 patients were in the two-way referral group and 200 patients in the core hospital-treated group. Compared with the core hospital-treated group, the two-way referral group had lower baseline LVEF (28 (22, 34)% vs. 31 (23, 36)%, P=0.021) and systolic blood pressure (116 (104, 125) mmHg vs. 121 (109, 134) mmHg (1 mmHg=0.133 kPa), P=0.010). The 12-month follow-up rate of the two-way referral group was higher than the core hospital-treated group (73.8% vs. 56.0%, P=0.004). No significant between-group differences were observed in drug utilization rate of β-blockers, ACEI/ARB/ARNI, or sodium-glucose cotransporter 2 inhibitors during follow-up (all P>0.05), while mineralocorticoid receptor antagonists use showed a declining trend in both groups. Although the core hospital-treated group had higher target dose achievement rates for β-blockers (65.4% vs. 49.3%, P=0.042) and ACEI/ARB/ARNI (79.8% vs. 65.8%, P=0.046) than the two-way referral group, multivariate logistic regression indicated that the two-way referral model was not a negative predictor for these outcomes (all P>0.05). Both groups showed improved NT-proBNP, LVEDd, and LVEF from baseline (all P<0.001) with no significant difference in trends between groups (all P>0.05). There was no significant difference in the composite incidence (7.6% vs. 6.5%, P=0.674) and cumulative incidence (log-rank P=0.684) of cardiovascular death and heart failure rehospitalization at 12 months between two groups. Conclusion:The two-way referral model demonstrates advantages in improving medication adherence, drug utilization rates, and targetdoseachievement rates among CHF patients. This model not only promotes cardiac functional recovery but also reduces risks of cardiovascular mortality and heart failure rehospitalization, achieving comparable therapeutic and management outcomes to those observed in core hospital-treated patients.

Purpose: To report a nationwide survey on neuroblastoma conducted by the Korean Association of Pediatric Surgeons (KAPS) in 2020. Methods: The clinical data of pediatric patients diagnosed with and treated for neuroblastoma from 2005 to 2019 in 19 hospitals of KAPS members were collected. Survival and prognostic factor analyses were performed using the log rank test and Cox proportional hazard analysis. A p-value <0.05 was considered significant. Results: A total of 669 patients with neuroblastoma were registered for the study. The results were presented and discussed at the 36th annual meeting of the KAPS, which was held in Seoul on August 21, 2020. Conclusion This study provides information on patient demographics, prognostic outcomes, and comprehensive treatment outcomes for neuroblastoma. The study is expected to be an important reference for improving pediatric surgeons’ understanding and treatment of neuroblastoma.

Objective: This study aimed to determine the impact of gestational age (GA) cut-off on the clinical outcome of congenital diaphragmatic hernia (CDH) and assess whether prematurity influences the predictive value of fetal lung volume measurement. Methods: We investigated the medical records of infants with CDH between January 2014 and August 2021. We classified the patients into term CDH (TCDH) and preterm CDH (PCDH) groups and compared their clinical characteristics, including fetal lung volume measured by the observed-toexpected lung-to-head ratio (O/E LHR). Results: Among 145 infants with CDH, 23 (15.9%) were preterm. Mean O/E LHR was significantly higher in survivors than in non-survivors with no difference between TCDH and PCDH groups.Mortality rate was significantly higher in infants with GA <34 weeks (80%) than in late preterm infants (16.7%). O/E LHR, rather than GA <34 weeks, was a risk factor predicting mortality in multivariate analyses. Predictive power of O/E LHR was high in the TCDH and PCDH groups, respectively. The incidence of chronic lung disease did not differ between PCDH and TCDH. Conclusion O/E LHR significantly predicted mortality in preterm infants, suggesting preterm birth alone should not be the determinant of early CDH treatment strategy.

Objective: This study aimed to determine the impact of gestational age (GA) cut-off on the clinical outcome of congenital diaphragmatic hernia (CDH) and assess whether prematurity influences the predictive value of fetal lung volume measurement. Methods: We investigated the medical records of infants with CDH between January 2014 and August 2021. We classified the patients into term CDH (TCDH) and preterm CDH (PCDH) groups and compared their clinical characteristics, including fetal lung volume measured by the observed-toexpected lung-to-head ratio (O/E LHR). Results: Among 145 infants with CDH, 23 (15.9%) were preterm. Mean O/E LHR was significantly higher in survivors than in non-survivors with no difference between TCDH and PCDH groups.Mortality rate was significantly higher in infants with GA <34 weeks (80%) than in late preterm infants (16.7%). O/E LHR, rather than GA <34 weeks, was a risk factor predicting mortality in multivariate analyses. Predictive power of O/E LHR was high in the TCDH and PCDH groups, respectively. The incidence of chronic lung disease did not differ between PCDH and TCDH. Conclusion O/E LHR significantly predicted mortality in preterm infants, suggesting preterm birth alone should not be the determinant of early CDH treatment strategy.

Objective: Neuroinflammation’s role is increasingly emphasized in the pathology of major depressive disorder (MDD), and its close association with the risk of suicide is being reported. The Forkhead Box O1 (FoxO1) gene is known to play a role in regulating mood and emotion and is associated with susceptibility to suicidality in relation to environmental stress. This research aims to explore the relationship between FoxO1 and the risk of suicide in individuals with MDD. Methods: We enrolled 127 healthy controls (HC) and 231 patients diagnosed with MDD, including 119 individuals with high suicide risk (HSR). All participants underwent the Hamilton Rating Scale for Depression Assessment and magnetic resonance imaging. Cortical thickness and white matter integrity were evaluated. Results: In the HSR group, cortical thinning was observed in the left triangular part of the inferior frontal gyrus and right transverse frontopolar gyrus compared to HC. Additionally, fractional anisotropy (FA) values were decreased in the left posterior thalamic radiation, sagittal stratum, and uncinate fasciculus. Although no differences were observed based on allele variations for the two FoxO1 single nucleotide polymorphisms (SNPs), those with the minor allele of FoxO1 rs34733279, especially in the HSR group, displayed increased cortical thinning and reduced FA values in the left cingulum. Conclusion Our study reveals close association between the minor allele of the FoxO1 gene rs34733279 and suicide risk in the left cingulum highlights the potential key role of the FoxO1 gene rs34733279 in the context of suicidal vulnerability. Further investigations are warranted to elucidate the underlying biological mechanisms.