Background Pulmonary hypertension (PH) is a common complication of bronchopulmonary dysplasia (BPD) in very-low-birth-weight infants (VLBWIs). Although recent studies have increased awareness that PH contributes significantly to the high morbidity and mortality of BPD, the risk factors and clinical characteristics for PH in VLBWIs are little known. Objectives To investigate the risk factors and clinical characteristics for BPD-associated pulmonary hypertension (BPD-PH) in VLBWIs. Methods A retrospective case–control observational study of VLBWIs with BPD admitted to a neonatal intensive care unit (NICU) over 4 years. According to echocardiograms confirming elevated pulmonary artery pressure after 28 days after birth, we divided BPD infants into PH group (n = 18) and non-PH group (n = 65). We compared pre- and postnatal characteristics between VLBWIs with or without PH. Multivariable logistic regression analysis was conducted with backward selection. Results A total of 83 infants with BPD were divided into PH group (n = 18) or non-PH group (n = 65). The average birth weight of the infants with BPD was 1078.1 g. Compared with those infants of the non-PH group, the birth weight of BPD-PH infants was significantly lower (968.1 ± 187.7 vs. 1108.5 ± 185.8, P = 0.006). Infants in the PH group had a higher incidence of patent ductus arteriosus (PDA) and underwent longer durations of oxygen therapy and mechanical ventilation compared to those in the non-PH group. In all subjects, birth weight (OR 0.995; 95% CI 0.991–0.999; P = 0.025) and PDA (OR 13.355; 95% CI 2.950–60.469; P = 0.001) were found to be specific risk factors for BPD-PH in this cohort. Conclusions The study shows PDA and birth weight are specific risk factors for BPD-PH in VLBWIs.

Bronchopulmonary dysplasia (BPD) is one of the main causes of chronic lung disease in premature infants. Acute lung injury following exposure to hyperoxia contributes to the development of BPD in preterm infants. The nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling pathway is an endogenous antioxidant defense mechanism that is involved in the pathogenesis of numerous hyperoxia-induced diseases.In the present study, the expression of Nrf2, Kelch-like ECH-associated protein 1 (Keap1) and NAD(P)H quinone oxidoreductase 1 enzyme (NQO1) was detected in A549 cells exposed to hyperoxia and transfection with small interfering RNA (siRNA) using reverse transcription-quantitative polymerase chain reaction and western blotting, and cellular apoptosis was detected using flow cytometry. The results demonstrated that apoptosis increased significantly following exposure of the cells to hyperoxia, and Nrf2, Keap1 and NQO1 expression levels were significantly upregulated under hyperoxic conditions. Furthermore, following transfection with Nrf2 siRNA, the expression levels of these genes were significantly downregulated and apoptosis was significantly increased compared with the respective values in untransfected cells. These findings suggest that the Nrf2-Keap1-antioxidant response element-NQO1 signaling pathway may play a protective role in hyperoxia-induced lung injury via the inhibition of apoptosis.

(1) Background: Reconstruction of Achilles tendon defects and prevention of postoperative tendon adhesions were two serious clinical problems. In the treatment of Achilles tendon defects, decellularized matrix materials and mesenchymal stem cells (MSCs) were thought to address both problems. (2) Methods: In vitro, cell adhesion, proliferation, and tenogenic differentiation of tendon-derived stem cells (TDSCs) on small intestinal submucosa (SIS) were evaluated. RAW264.7 was induced by culture medium of TDSCs and TDSCs–SIS scaffold groups. A rat Achilles tendon defect model was used to assess effects on tendon regeneration and antiadhesion in vivo. (3) Results: SIS scaffold facilitated cell adhesion and tenogenic differentiation of TDSCs, while SIS hydrogel coating promoted proliferation of TDSCs. The expression of TGF-β and ARG-1 in the TDSCs-SIS scaffold group were higher than that in the TDSCs group on day 3 and 7. In vivo, the tendon regeneration and antiadhesion capacity of the implanted TDSCs–SIS scaffold was significantly enhanced. The expression of CD163 was significantly highest in the TDSCs–SIS scaffold group; meanwhile, the expression of CD68 decreased more significantly in the TDSCs–SIS scaffold group than the other two groups. (4) Conclusion: This study showed that biologically prepared SIS scaffolds synergistically promote tendon regeneration with TDSCs and achieve antiadhesion through M2 polarization of macrophages.

Breast cancer is the most frequent type of malignancy, and the leading cause of cancer-related death in women across the globe. Exosomes are naturally derived 50-150 nm nanovesicles with a...