Objective:To investigate the impact of tumor origin (ventral pancreatic origin and dorsal pancreatic origin) on prognosis in patients with pancreatic head cancer.Methods:A retrospective analysis was performed on the clinical data of 150 patients with pancreatic head cancer who received surgical treatment at the First Affiliated Hospital of the Naval Medical University from October 2014 to December 2017. Among these patients, 92 were male and 58 were female, aged (61.2±8.8) years. The 150 patients were divided into two groups based on tumor origin: the ventral pancreatic cancer group ( n=72) and the dorsal pancreatic cancer group ( n=78). A comparative analysis of clinical, pathological, and imaging charac-teristics was conducted between the two groups. Univariate and multivariable Cox proportional hazards models were used to analyze the association between pancreatic head cancer origin and overall survival (OS). Results:Patients with pancreatic head carcinoma arising from the ventral and dorsal pancreas accounted for 48%(72/150) and 52%(78/150) of the study cohort, respectively. Pancreatic head carcinoma arising from the dorsal pancreas were more likely to show pathological features of pancreatic parenchymal atrophy [73.1%(57/78) vs. 47.2%(34/72), χ2=10.49, P=0.001] and pancreatitis [44.9%(35/78) vs. 29.2%(21/72), χ2=3.95, P=0.047]. In contrast, patients with pancreatic head carcinoma arising from the ventral pancreas was more frequently associated with contact with the superior mesenteric artery [25.0%(18/72) vs. 1.3%(1/78), χ2=19.04, P<0.001], perineural invasion [100%(72/72) vs. 88.5%(69/78), χ2=8.84, P=0.003], and positive surgical margins [15.3%(11/72) vs. 2.6%(2/78), χ2=7.65, P=0.006], with all differences statistically significant. The ventral pancreatic cancer group demonstrated cumulative survival rates of 33.2% and 0 at 1-year and 2-year postoperative intervals, respectively, while the dorsal pancreatic cancer group exhibited rates of 56.7% and 24.8% at the corresponding timepoints. Comparison of Kaplan-Meier survival curves between the two groups showed a statistically significant difference ( χ2=6.00, P=0.014). Multivariable Cox proportional hazards analysis identified dorsal pancreatic origin pancreatic head cancer as an independent predictor of increased mortality risk compared to ventral origin tumors ( HR=2.75, 95% CI: 1.52-4.98, P=0.001). Conclusion:The embryonic origin of pancreatic head cancer determines its clinical, pathological, and imaging heterogeneity, and pancreatic head cancer arising from the ventral pancreas demonstrates significantly worse prognostic outcomes compared to dorsal pancreatic origin.

Objective:To summarize the clinical and genetic characteristics of late-onset facioscapulohumeral muscular dystrophy type 1 (FSHD1) patients, and to compare the differences between late-onset and classic-onset FSHD1 patients.Methods:A retrospective analysis was conducted on the clinical and genetic data of genetically confirmed late-onset FSHD1 patients (age at onset30 years) between January 2007 and June 2024 from the Department of Neurology of Peking University First Hospital and the First Affiliated Hospital of Fujian Medical University. Classic-onset FSHD1 patients (10 yearsage at onset≤30 years) were matched 1∶1 according to sex and disease duration for comparison. The demographic information, the number of D4Z4 repeat units, the distal D4Z4 methylation levels, FSHD Clinical Score (CS), Clinical Severity Score (CSS), and Age-Corrected Clinical Severity Score (ACSS) of these patients were collected. Survival analysis was performed to compare the outcome of lower extremity involvement between late-onset and classic-onset FSHD1 patients. The correlation of the number of D4Z4 repeat units and D4Z4 methylation level with CS and ACSS was analyzed in late-onset FSHD1 patients.Results:A total of 61 patients with late-onset FSHD1 were enrolled, 33 (54.1%) of whom are female, with an age of 54.0 (46.0, 62.0) years and a disease duration of 14.0 (5.5, 22.5) years. Compared to classic-onset FSHD1 patients, late-onset patients exhibited significantly lower CS [7.0 (5.6, 8.4) vs 6.0 (4.4, 7.7), U=1 416.000, P=0.013], CSS [3.0 (2.8, 3.3) vs 3.0 (2.0, 4.0), U=2 352.000, P=0.010], and ACSS [189.2 (137.1, 241.3) vs 96.8 (61.3, 132.2), U=3 225.500, P0.001], and higher proportion of patients with limb girdle involvement but no facial muscle involvement [18.0% (11/61) vs 6.6% (4/61), χ2=3.725, P=0.054]. Kaplan-Meier survival analysis showed that the onset age of lower extremity involvement in late-onset patients (45 years, 95% CI 42-48 years) was significantly higher than that in classic-onset patients (24 years, 95% CI 21-27 years, χ2=61.012, P0.001). The duration from symptom onset to lower extremity involvement in late-onset patients (15 years, 95% CI 10-20 years) was significantly longer than that in classic-onset patients (8 years, 95% CI 3-13 years, χ2=9.105, P=0.003). Late-onset FSHD1 patients carried higher average distal D4Z4 methylation levels compared to those with classic-onset FSHD1 [46.68% (40.79%,52.57%) vs 41.02% (34.03%,48.00%), U=1 378.500, P=0.014]. Among late-onset FSHD1 patients, cytosine-phosphate-guanine 6 (CpG6) methylation levels were significantly negatively correlated with ACSS ( r=-0.278, P=0.025); the number of D4Z4 repeat units were significantly negatively correlated with ACSS ( r=-0.272, P=0.034);CpG6 methylation levels were significantly negatively correlated with CS ( r=-0.441, P=0.003), while no correlation was found between number of D4Z4 repeat units and CS ( r=-0.161, P=0.310). Conclusions:Compared with classic-onset FSHD1 patients, late-onset FSHD1 patients are associated with a higher degree of distal D4Z4 methylation, along with a milder muscle weakness phenotype, slower disease progression and a higher proportion of cases without facial muscle involvement. The age at onset can be used as a marker of the severity and prognosis in FSHD1.

Objective:A prognosis prediction model for pancreatic cancer was constructed based on multi-scale radiomics combined with deep learning, and the prediction effect of the model was evaluated.Methods:A retrospective analysis was conducted on the clinical data of 215 patients who underwent radical resection of pancreatic cancer at the First Affiliated Hospital of Naval Medical University from January 2017 to December 2017. Among them, 134 were male and 81 were female, with an age of (61.9±9.2) years. Patients were randomly divided into the training set ( n=151) and the test set ( n=64) in a ratio of 7: 3. Habitat features, peritumoral radiomics features, 3D radiomics features, and 2.5D deep learning features were extracted from preoperative CT images respectively. After feature screening, a survival prediction model was constructed using the CoxBoost machine learning algorithm that integrated the Boosting algorithm and the Cox proportional hazards model. The performance of the model was evaluated using the area under the time-dependent receiver operating characteristic curve and the consistency index. The clinical benefits of the model were evaluated using decision curve analysis. The survival curves were plotted using the Kaplan-Meier method, and the log-rank test was used for the comparison of survivals between groups. Results:The LASSO, random forest and extreme gradient boosting models were each used to screen out the top 10 most important features and take the union, ultimately obtaining 20 radiomics features for modeling. In the training set and test set, the consistency index of the CoxBoost model in predicting overall survival was 0.717 (95% CI: 0.669-0.765) and 0.688 (95% CI: 0.610-0.766), respectively, and the area under the curve for predicting overall survival at 1, 2, and 3 years after surgery was 0.830 (95% CI: 0.752-0.898), 0.753 (95% CI: 0.665-0.833), 0.828 (95% CI: 0.735-0.908) and 0.690 (95% CI: 0.549-0.824), 0.780 (95% CI: 0.649-0.887 and 0.793 (95% CI: 0.660-0.897), respectively. The area under the curve for predicting long-term survival after surgery (≥40 months) was above 0.8. Based on the optimal cutoff value of -0.19 for the predicted value of the CoxBoost model calculated by the R package " survminer", the patients were divided into high-risk (predicted value >-0.19) and low-risk (predicted value <-0.19) groups. In both the training set and the test set, the survival of patients in the low-risk group was better than that in the high-risk group (training set: χ2=39.01, P<0.001; test set: χ2=12.34, P<0.001). The median survival period of patients in the high-risk group was lower than that in the low-risk group (training set: 15.80 vs 34.07 months; test set: 16.87 vs 43.07; months). Decision curve analysis shows that patients obtain survival benefit when the threshold probability of the training set is greater than 0.25 and that of the test set is greater than 0.45. Conclusion:The CoxBoost model has a good predictive ability for the overall survival of pancreatic cancer patients after surgery and can effectively screen out patient subgroups that may significantly benefit from surgical treatment.

OBJECTIVES: This study aimed to explore the expression of lysosomal-associated membrane protein 5 (LAMP5) and microRNA (miR)-302a-3p in oral squamous cell carcinoma (OSCC) and their functional mechanism on the invasion and metastasis of OSCC. METHODS: The expression of LAMP5 in OSCC and its sensitivity as a prognostic indicator were analyzed on the basis of The Cancer Genome Atlas database. Western blot, quantitative reverse transcription polymerase chain reaction, and cell immunocytochemistry were used to detect the expression of LAMP5 in OSCC tissues and cells. The effect of LAMP5 on the proliferation, migration, and invasion of OSCC cells was evaluated through cell counting kit-8, immunocytochemistry, migration, and invasion assays, respectively. The miRNA targeting prediction websites were used to predict the miR that regulates LAMP5 and verify the targeted regulatory effect of miR-302a-3p on LAMP5. The effect of LAMP5 knockdown on OSCC tumor growth was evaluated in a nude mouse tumorigenesis model. RESULTS: LAMP5 was highly expressed in OSCC tissues and cells. It showed high sensitivity in the early diagnosis of OSCC. LAMP5 knockdown significantly inhibited the proliferation, migration, and invasion of OSCC cells, whereas LAMP5 overexpression increased these cell activities. The expression of LAMP5 was regulated by miR-302a-3p. In vivo, LAMP5 knockdown significantly inhibited the growth of OSCC tumor. CONCLUSIONS LAMP5 promotes the malignant progression of OSCC by enhancing the proliferation, migration, and invasion of OSCC cells. The expression of LAMP5 is negatively regulated by miR-302a-3p.
MicroRNAs/metabolism* ; Mouth Neoplasms/metabolism* ; Humans ; Animals ; Carcinoma, Squamous Cell/genetics* ; Neoplasm Invasiveness ; Cell Proliferation ; Mice, Nude ; Cell Movement ; Lysosomal Membrane Proteins/genetics* ; Mice ; Cell Line, Tumor ; Neoplasm Metastasis

Objective: To investigate the value of metagene next⁃generation sequencing ( mNGS) in the detection of pathogens in patients with pulmonary infection. Methods: A retrospective analysis was performed on clinical data from 434 patients with pulmonary infections admitted over the past four years. Based on the presence of underlying comorbidities , patients were divided into underlying disease group (n = 262) and non⁃underlying disease group (n = 172) . Pathogen detection was conducted using both mNGS and conventional tests. Clinical and laboratory parameters , radiographic findings , and pathogen detection results were systematically analyzed. The diagnostic performance of the two methods in identifying causative pathogens of pulmonary infections was compared. Results: The positive rate of mNGS in 434 patients was higher than that of conventional tests , and the difference was statisti⁃cally significant (P < 0. 05) . The efficacy of mNGS in detecting bacteria and viruses was significantly higher than that of conventional tests , and the difference was statistically significant (P < 0. 05) . Although the fungal detection rate of mNGS was higher than that of conventional tests , the difference was not statistically significant. Among them , the detection rates of Mycobacterium tuberculosis , Mycoplasma pneumoniae , Haemophilus influenzae , Strepto⁃ coccus pneumoniae , Streptococcus constellation , Staphylococcus aureus and Aspergillus fumigatus were significantly higher than those of conventional tests , and the difference was statistically significant (P < 0. 05) . Subgroup analy- sis showed that the proportion of males , hospital stay , smoking prevalence and average age in the underlying dis- ease group were higher than those in the non-underlying disease group , and the difference was statistically signifi- cant (P < 0. 05) , while there were no significant differences in antibiotic use and endotracheal intubation rate be- tween the two groups. The most common pathogens detected by mNGS in the underlying disease group were Myco⁃ bacterium tuberculosis , Haemophilus influenzae , Streptococcus pneumoniae , Pseudomonas aeruginosa , human herpes⁃ virus type 4 and Aspergillus fumigatus , while the most common pathogens in the non-underlying disease group were Mycobacterium tuberculosis , Haemophilus influenzae , Streptococcus pneumoniae , Mycoplasma pneumoniae and Kleb⁃ siella pneumoniae. The positive rate of mNGS in the two groups was significantly higher than that of conventional tests , and the difference was statistically significant (P < 0. 05) , while the difference in the positive rate of mNGS between the two groups was not statistically significant. Conclusion mNGS has significant advantages over con- ventional tests of pathogen in lung infection , and is less affected by underlying diseases , which can provide an etio- logical basis for lung infection.

Objective:To investigate the impact of tumor origin (ventral pancreatic origin and dorsal pancreatic origin) on prognosis in patients with pancreatic head cancer.Methods:A retrospective analysis was performed on the clinical data of 150 patients with pancreatic head cancer who received surgical treatment at the First Affiliated Hospital of the Naval Medical University from October 2014 to December 2017. Among these patients, 92 were male and 58 were female, aged (61.2±8.8) years. The 150 patients were divided into two groups based on tumor origin: the ventral pancreatic cancer group ( n=72) and the dorsal pancreatic cancer group ( n=78). A comparative analysis of clinical, pathological, and imaging charac-teristics was conducted between the two groups. Univariate and multivariable Cox proportional hazards models were used to analyze the association between pancreatic head cancer origin and overall survival (OS). Results:Patients with pancreatic head carcinoma arising from the ventral and dorsal pancreas accounted for 48%(72/150) and 52%(78/150) of the study cohort, respectively. Pancreatic head carcinoma arising from the dorsal pancreas were more likely to show pathological features of pancreatic parenchymal atrophy [73.1%(57/78) vs. 47.2%(34/72), χ2=10.49, P=0.001] and pancreatitis [44.9%(35/78) vs. 29.2%(21/72), χ2=3.95, P=0.047]. In contrast, patients with pancreatic head carcinoma arising from the ventral pancreas was more frequently associated with contact with the superior mesenteric artery [25.0%(18/72) vs. 1.3%(1/78), χ2=19.04, P<0.001], perineural invasion [100%(72/72) vs. 88.5%(69/78), χ2=8.84, P=0.003], and positive surgical margins [15.3%(11/72) vs. 2.6%(2/78), χ2=7.65, P=0.006], with all differences statistically significant. The ventral pancreatic cancer group demonstrated cumulative survival rates of 33.2% and 0 at 1-year and 2-year postoperative intervals, respectively, while the dorsal pancreatic cancer group exhibited rates of 56.7% and 24.8% at the corresponding timepoints. Comparison of Kaplan-Meier survival curves between the two groups showed a statistically significant difference ( χ2=6.00, P=0.014). Multivariable Cox proportional hazards analysis identified dorsal pancreatic origin pancreatic head cancer as an independent predictor of increased mortality risk compared to ventral origin tumors ( HR=2.75, 95% CI: 1.52-4.98, P=0.001). Conclusion:The embryonic origin of pancreatic head cancer determines its clinical, pathological, and imaging heterogeneity, and pancreatic head cancer arising from the ventral pancreas demonstrates significantly worse prognostic outcomes compared to dorsal pancreatic origin.

Objective:To summarize the clinical and genetic characteristics of late-onset facioscapulohumeral muscular dystrophy type 1 (FSHD1) patients, and to compare the differences between late-onset and classic-onset FSHD1 patients.Methods:A retrospective analysis was conducted on the clinical and genetic data of genetically confirmed late-onset FSHD1 patients (age at onset30 years) between January 2007 and June 2024 from the Department of Neurology of Peking University First Hospital and the First Affiliated Hospital of Fujian Medical University. Classic-onset FSHD1 patients (10 yearsage at onset≤30 years) were matched 1∶1 according to sex and disease duration for comparison. The demographic information, the number of D4Z4 repeat units, the distal D4Z4 methylation levels, FSHD Clinical Score (CS), Clinical Severity Score (CSS), and Age-Corrected Clinical Severity Score (ACSS) of these patients were collected. Survival analysis was performed to compare the outcome of lower extremity involvement between late-onset and classic-onset FSHD1 patients. The correlation of the number of D4Z4 repeat units and D4Z4 methylation level with CS and ACSS was analyzed in late-onset FSHD1 patients.Results:A total of 61 patients with late-onset FSHD1 were enrolled, 33 (54.1%) of whom are female, with an age of 54.0 (46.0, 62.0) years and a disease duration of 14.0 (5.5, 22.5) years. Compared to classic-onset FSHD1 patients, late-onset patients exhibited significantly lower CS [7.0 (5.6, 8.4) vs 6.0 (4.4, 7.7), U=1 416.000, P=0.013], CSS [3.0 (2.8, 3.3) vs 3.0 (2.0, 4.0), U=2 352.000, P=0.010], and ACSS [189.2 (137.1, 241.3) vs 96.8 (61.3, 132.2), U=3 225.500, P0.001], and higher proportion of patients with limb girdle involvement but no facial muscle involvement [18.0% (11/61) vs 6.6% (4/61), χ2=3.725, P=0.054]. Kaplan-Meier survival analysis showed that the onset age of lower extremity involvement in late-onset patients (45 years, 95% CI 42-48 years) was significantly higher than that in classic-onset patients (24 years, 95% CI 21-27 years, χ2=61.012, P0.001). The duration from symptom onset to lower extremity involvement in late-onset patients (15 years, 95% CI 10-20 years) was significantly longer than that in classic-onset patients (8 years, 95% CI 3-13 years, χ2=9.105, P=0.003). Late-onset FSHD1 patients carried higher average distal D4Z4 methylation levels compared to those with classic-onset FSHD1 [46.68% (40.79%,52.57%) vs 41.02% (34.03%,48.00%), U=1 378.500, P=0.014]. Among late-onset FSHD1 patients, cytosine-phosphate-guanine 6 (CpG6) methylation levels were significantly negatively correlated with ACSS ( r=-0.278, P=0.025); the number of D4Z4 repeat units were significantly negatively correlated with ACSS ( r=-0.272, P=0.034);CpG6 methylation levels were significantly negatively correlated with CS ( r=-0.441, P=0.003), while no correlation was found between number of D4Z4 repeat units and CS ( r=-0.161, P=0.310). Conclusions:Compared with classic-onset FSHD1 patients, late-onset FSHD1 patients are associated with a higher degree of distal D4Z4 methylation, along with a milder muscle weakness phenotype, slower disease progression and a higher proportion of cases without facial muscle involvement. The age at onset can be used as a marker of the severity and prognosis in FSHD1.

Objective:A prognosis prediction model for pancreatic cancer was constructed based on multi-scale radiomics combined with deep learning, and the prediction effect of the model was evaluated.Methods:A retrospective analysis was conducted on the clinical data of 215 patients who underwent radical resection of pancreatic cancer at the First Affiliated Hospital of Naval Medical University from January 2017 to December 2017. Among them, 134 were male and 81 were female, with an age of (61.9±9.2) years. Patients were randomly divided into the training set ( n=151) and the test set ( n=64) in a ratio of 7: 3. Habitat features, peritumoral radiomics features, 3D radiomics features, and 2.5D deep learning features were extracted from preoperative CT images respectively. After feature screening, a survival prediction model was constructed using the CoxBoost machine learning algorithm that integrated the Boosting algorithm and the Cox proportional hazards model. The performance of the model was evaluated using the area under the time-dependent receiver operating characteristic curve and the consistency index. The clinical benefits of the model were evaluated using decision curve analysis. The survival curves were plotted using the Kaplan-Meier method, and the log-rank test was used for the comparison of survivals between groups. Results:The LASSO, random forest and extreme gradient boosting models were each used to screen out the top 10 most important features and take the union, ultimately obtaining 20 radiomics features for modeling. In the training set and test set, the consistency index of the CoxBoost model in predicting overall survival was 0.717 (95% CI: 0.669-0.765) and 0.688 (95% CI: 0.610-0.766), respectively, and the area under the curve for predicting overall survival at 1, 2, and 3 years after surgery was 0.830 (95% CI: 0.752-0.898), 0.753 (95% CI: 0.665-0.833), 0.828 (95% CI: 0.735-0.908) and 0.690 (95% CI: 0.549-0.824), 0.780 (95% CI: 0.649-0.887 and 0.793 (95% CI: 0.660-0.897), respectively. The area under the curve for predicting long-term survival after surgery (≥40 months) was above 0.8. Based on the optimal cutoff value of -0.19 for the predicted value of the CoxBoost model calculated by the R package " survminer", the patients were divided into high-risk (predicted value >-0.19) and low-risk (predicted value <-0.19) groups. In both the training set and the test set, the survival of patients in the low-risk group was better than that in the high-risk group (training set: χ2=39.01, P<0.001; test set: χ2=12.34, P<0.001). The median survival period of patients in the high-risk group was lower than that in the low-risk group (training set: 15.80 vs 34.07 months; test set: 16.87 vs 43.07; months). Decision curve analysis shows that patients obtain survival benefit when the threshold probability of the training set is greater than 0.25 and that of the test set is greater than 0.45. Conclusion:The CoxBoost model has a good predictive ability for the overall survival of pancreatic cancer patients after surgery and can effectively screen out patient subgroups that may significantly benefit from surgical treatment.

Objective:To describe the current status and trends in the outcomes and care practices of extremely preterm infants at 22-25 weeks′ gestation age from the Chinese Neonatal Network (CHNN) from 2019 to 2021.Methods:This cross-sectional study used data from the CHNN cohort of very preterm infants. All 963 extremely preterm infants with gestational age between 22-25 weeks who were admitted to neonatal intensive care units (NICU) of the CHNN from 2019 to 2021 were included. Infants admitted after 24 hours of life or transferred to non-CHNN hospitals were excluded. Perinatal care practices, survival rates, incidences of major morbidities, and NICU treatments were described according to different gestational age groups and admission years. Comparison among gestational age groups was conducted using χ2 and Kruskal-Wallis tests. Trends by year were evaluated by Cochran-Armitage and Jonckheere-Terpstra tests for trend. Results:Of the 963 extremely preterm infants enrolled, 588 extremely preterm infants (61.1%) were male. The gestational age was 25.0 (24.4, 25.6) weeks, with 29 extremely preterm infants (3.0%), 88 extremely preterm infants (9.1%), 264 extremely preterm infants (27.4%), and 582 extremely preterm infants (60.4%) at 22, 23, 24, and 25 weeks of gestation age, respectively. The birth weight was 770 (680, 840) g. From 2019 to 2021, the number of extremely preterm infants increased each year (285, 312, and 366 extremely preterm infants, respectively). Antenatal steroids and magnesium sulfate were administered to 67.7% (615/908) and 51.1% (453/886) mothers of extremely preterm infants. In the delivery room, 20.8% (200/963) and 69.5% (669/963) extremely preterm infants received noninvasive positive end-expiratory pressure support and endotracheal intubation. Delayed cord clamping and cord milking were performed in 19.0% (149/784) and 30.4% (241/794) extremely preterm infants. From 2019 to 2021, there were significant increases in the usage of antenatal steroids, antenatal magnesium sulfate, and delivery room noninvasive positive-end expiratory pressure support (all P<0.05). Overall, 349 extremely preterm infants (36.2%) did not receive complete care, 392 extremely preterm infants (40.7%) received complete care and survived to discharge, and 222 extremely preterm infants (23.1%) received complete care but died in hospital. The survival rates for extremely preterm infants at 22, 23, 24 and 25 weeks of gestation age were 10.3% (3/29), 23.9% (21/88), 33.0% (87/264) and 48.3% (281/582), respectively. From 2019 to 2021, there were no statistically significant trends in complete care, survival, and mortality rates (all P>0.05). Only 11.5% (45/392) extremely preterm infants survived without major morbidities. Moderate to severe bronchopulmonary dysplasia (67.3% (264/392)) and severe retinopathy of prematurity (61.5% (241/392)) were the most common morbidities among survivors. The incidences of severe intraventricular hemorrhage or periventricular leukomalacia, necrotizing enterocolitis, and sepsis were 15.3% (60/392), 5.9% (23/392) and 19.1% (75/392), respectively. Overall, 83.7% (328/392) survivors received invasive ventilation during hospitalization, with a duration of 22 (10, 42) days. The hospital stay for survivors was 97 (86, 116) days. Conclusions:With the increasing number of extremely preterm infants at 22-25 weeks′ gestation admitted to CHNN NICU, the survival rate remained low, especially the rate of survival without major morbidities. Further quality improvement initiatives are needed to facilitate the implementation of evidence-based care practices.

Objective:To investigate the current status, trends, and differences among institutions in the application of delivery room continuous positive airway pressure (DRCPAP) for very preterm infants treated in the institutions in the Chinese Neonatal Network (CHNN). Also, to explore the impact of DRCPAP on the outcomes of very preterm infants in China.Methods:A retrospective cohort study was conducted. Based on the CHNN very preterm infant cohort, very preterm infants (gestational ages ranging from 25 weeks +0 to 31 weeks +6) born in-hospital and treated in 79 tertiary neonatal intensive care units (NICUs) participating in the CHNN from 2019 to 2021 were included. The usage rates of DRCPAP in different hospitals, as well as gestational ages and years, were described. Data were analyzed using the Chi-square test (or Fisher's exact test) or t-test. A multivariate logistic regression model was established to explore the correlation between DRCPAP and clinical outcomes. Results:(1) A total of 18 048 very preterm infants were included. Among them, 3 666 (20.3%) received DRCPAP, and 14 382 (79.7%) did not. (2) The usage rate of DRCPAP for very preterm infants among different institutions is from 0.0% to 94.5%. Fourteen institutions did not use DRCPAP, and 55 institutions had a usage rate below 30%. The usage rate of DRCPAP in very preterm infants increased annually, from 13.8% (818/5 916) in 2019 to 26.0% (1 583/6 097) in 2021 ( χ2trend=122.00, P<0.001). (3) The DRCPAP group had higher rates of maternal assisted reproductive technology pregnancy, chorioamnionitis, a full course of antenatal corticosteroids, gestational diabetes, fetal distress, antenatal magnesium sulfate use, and cesarean delivery compared to the non-DRCPAP group [20.3% (744/3 665) vs. 17.6% (2 529/14 369), χ2=14.45; 23.0% (695/3 021) vs. 16.4% (1 956/11 926), χ2=72.57; 57.1% (2 090/3 660) vs. 54.3% (7 766/14 302), χ2=9.55; 23.0% (844/3 669) vs. 20.7% (2 969/14 342), χ2=9.77; 8.7% (319/3 666) vs. 7.0% (1 006/14 371), χ2=12.51; 87.1% (3 186/3 657) vs. 82.0% (11 736/14 312), χ2=81.38; 63.5% (2 327/3 664) vs. 60.7% (8 722/14 369), χ2=9.59; all P<0.05]. While the incidence of hypertensive disorders of pregnancy and the proportion of infants not using antenatal corticosteroids were lower in the non-DRCPAP group [17.1% (626/3 660) vs. 22.6% (3 183/14 084), χ2=44.70; 14.2% (520/3 661) vs. 19.7% (2 814/14 284), χ2=57.34; all P<0.05]. The DRCPAP group had lower birth weight and gestational age, higher 1 min and 5 min Apgar scores, and lower neonatal transport stabilization index scores [(1 308±314) g vs. (1 325±315) g, t=2.90; (29.5±1.7) weeks vs. (29.7±1.6) weeks, t=3.96; (7.9±1.8) scores vs. (7.6±1.9) scores, t=－9.80; (9.0±1.1) scores vs. (8.7±1.3) scores, t=－13.01; (11.0±9.4) scores vs. (13.1±9.8) scores, t=11.31; all P<0.05]. The incidence of early-onset sepsis was higher in the DRCPAP group than in the non-DRCPAP group [1.8% (68/3 578) vs. 1.3% (193/14 296), adjusted OR (95% CI): 1.417 (1.028-1.955)], while the rates of tracheal intubation within 72 hours, PS use, invasive mechanical ventilation, mortality, admission hypothermia, grade Ⅲ-Ⅳ intracranial hemorrhage, and stage≥3 ROP were all lower in the DRCPAP group compared to the non-DRCPAP group [22.6% (830/3 666) vs. 36.9% (5 310/14 374), adjusted OR (95% CI): 0.499 (0.448-0.555); 53.1% (1 947/3 666) vs. 58.3% (8 388/14 377), adjusted OR (95% CI): 0.764 (0.697-0.836); 30.1% (1 104/3 662) vs. 43.9% (6 307/14 366), adjusted OR (95% CI): 0.539 (0.487-0.595); 7.4% (274/3 666) vs. 10.6% (1 526/14 342), adjusted OR (95% CI): 0.709 (0.601-0.836); 57.5% (2 103/3 657) vs. 66.5% (9 501/14 287), adjusted OR (95% CI): 0.722 (0.661-0.788); 3.0% (101/3 366) vs. 5.9% (763/12 932)], adjusted OR (95% CI): 0.525 (0.412-0.669); 2.2% (65/2 954) vs. 3.3% (367/11 121), adjusted OR (95% CI): 0.692 (0.505-0.947); all P<0.05]. There were no statistically significant differences between the two groups in the incidence rates of BPD at a corrected gestational age of 36 weeks, patent ductus arteriosus ligation, spontaneous intestinal perforation, and pneumothorax. Conclusions:Domestically, the application of DRCPAP might be related to a decrease in the demand for invasive ventilation, the use of surfactants, and mortality, but it might not reduce the occurrence of bronchopulmonary dysplasia, at a corrected gestational age of 36 weeks. In recent years, the use of DRCPAP in very premature infants in China has increased, but the overall usage rate is still low, and there are significant differences between units, requiring continuous quality improvement.