Objective To study the expression of high mobility group box protein 4 (SOX4) and β-catenin in lung tissues of preterm rats with hyperoxia exposure,and to study its significance.Method One-day-old preterm Sprague Dawley rats were randomly assigned into 4 groups:95％ hyperoxia group,70％ hyperoxia group,45％ hyperoxia group and air group.After three days,pathological changes of the lung tissues were observed by hematoxylin eosin staining,the mRNA expressions of SOX4 and β-catenin in lung tissues were detected by semi-quantitative reverse transcription polymerase chain reaction,and the protein expressions of SOX4 and β-catenin in the lung tissues were measured by western blot.Result The structure of lung tissues in air group was normal.45％ hyperoxia group represented mainly effusion and inflammatory cell infiltration,70％ and 95％ hyperoxia group showed acute lung injury characterized by inflammatory cell infiltration,hyperaemia,hemorrhagic change,disorganization and collapse of alveolar.The expressions of SOX4 mRNA and protein were highly elevated in all hyperoxia groups than that in air group (P ＜ 0.01);Compared with 45％ hyperoxia group,the expressions of SOX4 mRNA and protein were higher in 95％ hyperoxia group (P ＜ 0.01).β-catenin mRNA,total β-catenin protein and nuclear β-catenin protein were also highly elevated in hyperoxia groups compared with air group (P ＜ 0.05).Compared with 45％ hyperoxia group,the expressions of β-catenin mRNA and total β-catenin protein were also highly raised in 70％ hyperoxia group and 95％ hyperoxia group (P ＜ 0.05).The expression of nuclear β-catenin protein was higher in 95％ hyperoxia group than that in 45％ hyperoxia group (P ＜ 0.01).Conclusion The mRNA and protein expressions of SOX4 and β-catenin in lung tissues of preterm rats were increased by hyperoxia exposure.This mechanism may take part in hyperoxia-induced preterm rats lung injury.

OBJECTIVETo investigate the HLA-A, -B allele polymorphism in the Luoba ethnic population.

METHODSHLA-A, -B DNA types in 92 healthy individuals of Luoba nationality in the Linzhi area, Tibet Autonomous Region, were investigated by polymerase chain reaction-sequence specific oligo-nucleotide (PCR-SSO).

RESULTSTen alleles at HLA-A locus, and 19 alleles at HLA-B locus in Luoba ethnic group were detected. Of the 10 HLA-A alleles detected, the three most common alleles were HLA-A*11(allele frequency: 36.40%), -A*02 (25.50%), -A*24 (23.90%), and they covered 85.80% of the total HLA-A alleles detected from the Luoba ethnic group. Of the 19 HLA-B alleles detected, the three most common alleles were HLA-B*40 (27.20%), -B*15 (11.40%) and -B*38(10.90%), and they covered 49.50% of the total -B alleles detected in the Luoba ethnic group.

CONCLUSIONThe distribution of HLA-A, -B allele polymorphism in the Luoba nationality is distinctive, but some of the gene distribution in the Luoba group is nearer to that in the Tibetan group. These are consistent with the results of ethnological, historical and sociological researches.

Alleles ; Ethnic Groups ; genetics ; Gene Frequency ; HLA Antigens ; genetics ; HLA-B Antigens ; genetics ; Humans ; Polymerase Chain Reaction ; Polymorphism, Genetic ; genetics ; Tibet

Objective:To study the risk factors of failure using nasal high frequency oscillatory ventilation (nHFOV) as initial therapy in the treatment of respiratory distress syndrome (RDS) in very low birth weight infants (VLBWIs).Methods:From January 2018 to December 2021, VLBWIs with RDS initially supported by nHFOV in NICU of our hospital were retrospectively analyzed. They were assigned into success and failure groups according to the ventilation efficacy. Demographic data and clinical outcomes of the two groups were compared. Risk factors of initial nHFOV failure were analyzed using binary Logistic regression method.Results:A total of 135 infants were included, including 103 in the success group and 32 in the failure group. The initial nHFOV failure rate was 23.7%. The failure group had lower pH (7.26±0.09 vs. 7.33±0.08) and PaO 2 [61.0 (49.6, 77.2) mmHg vs. 83.6 (64.4, 99.0) mmHg] than the success group ( P<0.05) and higher PaCO 2 than the success group [49.0 (42.3, 58.1) mmHg vs. 43.4 (36.0, 50.0) mmHg] ( P<0.05). Using PaCO 2 as predictor, the area under the curve (AUC) was 0.682 (95% CI 0.575-0.788) and the cut-off value was 44.8 mmHg for nHFOV failure and the AUC was 0.716 (95% CI 0.615-0.817) and the cut-off value was 67.1 mmHg for nHFOV success. The incidences of early onset sepsis (EOS), shock within 3 d and hemodynamically significant patent ductus arteriosus (hsPDA) in the failure group were significantly higher than the success group (40.6% vs. 7.8%, 53.1% vs. 2.9%, 31.3% vs. 13.6%, P<0.05, respectively). Binary logistic regression analysis found that PaO 2<67.1 mmHg ( OR=5.458,95% CI 1.730-17.220) on the first blood gas analysis and shock within 3 d ( OR=26.585,95% CI 3.854-183.396) were independent risk factors for initial nHFOV failure ( P<0.05). Conclusions:The failure of initial nHFOV is correlated with the first blood gas parameters, EOS, hsPDA and shock within 3 d. Shock within 3 d and low PaO 2(<67.1 mmHg) were independent risk factors for initial nHFOV failure.

Objective:To study the safety and feasibility of application of delayed umbilical cord clamping (DCC) in very preterm and extremely preterm infants.Methods:Based on the previous improvement projects of temperature management and respiratory support, we conducted a prospective study on the effect of umbilical cord clamping quality improvement project using the clinical data of very preterm and extremely preterm infants admitted to Guangdong Maternal and Child Health Hospital. The infants admitted from July to December 2020 who underwent immediate umbilical cord clamping (ICC) were included in the ICC group, and the infants admitted from January to June 2021 who underwent DCC were involved in the DCC group. The incidence of asphyxia, hypothermia, endotracheal intubation within 24 h after birth, endotracheal intubation within 72 h after birth, bronchopulmonary dysplasia and other complications, mechanical ventilation duration and total oxygen therapy duration were compared between the two groups.Results:A total of 45 cases were included in ICC group and 54 cases in DCC group. The gestational age of the two groups was (29.3±1.7) weeks and (29.6±1.4) weeks, and the birth weight was (1 250±332) g and (1 257±306) g. The differences were not statistically significant ( P>0.05). There were no significant differences between the two groups in the incidence of asphyxia, hypothermia, bronchopulmonary dysplasia and other complications related to preterm infants, tracheal intubation rates within 24 and 72 h, and the neonatal temperature at admission to NICU ( P>0.05). Conclusions:Delayed umbilical cord clamping does not increase the risks of asphyxia, hypothermia or invasive respiratory support in very preterm and extremely preterm infants.