Shape memory hydrogels with remodelable permanent shapes and programmable cold-induced shape recovery behavior.

Most shape memory polymers apply glass transition or crystallization of domains to fix temporary shapes and shape recovery is induced by heating, which hinders their application under heat-intolerant conditions. Moreover, the permanent shapes of polymers normally cannot be altered arbitrarily after fabrication. Herein, we present a novel shape memory hydrogel with a remodelable permanent shape and programmable cold-induced shape recovery behavior. Poly(acrylic acid) (PAA) hydrogel is prepared in the presence of diethylenetriamine (DETA) and subsequently treated with calcium acetate (Ca(Ac)2). The charge-assisted hydrogen bonding between PAA and DETA imparts the hydrogel with remodelability, while the heat-induced hydrophobic aggregation of polymer chains and acetate groups results in shape fixation by heating and shape recovery by cooling. Afterwards, programmable deformable devices are obtained by assembling hydrogel blocks with different concentrations of Ca(Ac)2. This design strategy promotes the development of shape memory polymers with diverse potential applications.

The multifaceted role of placental growth factor in the pathogenesis and progression of bronchial asthma and pulmonary fibrosis: Therapeutic implications.

Placental growth factor (PlGF) is a glycosylated dimeric protein that is homologous to vascular endothelial growth factor (VEGF). PlGF expression is upregulated in patients with bronchial asthma, suggesting that it plays a role in the pathogenesis of asthma. Bronchial asthma is characterized by chronic airway inflammation and airway hyperresponsiveness (AHR). After recurrent asthma attacks, pulmonary fibrosis develops and leads to airway remodeling and a further decline in lung function. In this review, we focused on the pivotal role of PlGF in chronic airway inflammation, AHR, and airway remodeling during bronchial asthma. Furthermore, we summarized data showing that PlGF may be a potential therapeutic target in bronchial asthma.

Bioinformatic analysis and validation of microRNA-508-3p as a protective predictor by targeting NR4A3/MEK axis in pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) featured a debilitating progressive disorder. Here, we intend to determine diagnosis-valuable biomarkers for PAH and decode the fundamental mechanisms of the biological function of these markers. Two mRNA microarray profiles (GSE70456 and GSE117261) and two microRNA microarray profiles (GSE55427 and GSE67597) were mined from the Gene Expression Omnibus platform. Then, we identified the differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs), respectively. Besides, we investigated online miRNA prediction tools to screen the target gene of DEMs. In this study, 185 DEGs and three common DEMs were screened as well as 1266 target genes of the three DEMs were identified. Next, 16 overlapping dysregulated genes from 185 DEGs and 1266 target gene were obtained. Meanwhile, we constructed the miRNA gene regulatory network and determined miRNA-508-3p-NR4A3 pair for deeper exploring. Experiment methods verified the functional expression of miR-508-3p in PAH and its signalling cascade. We observed that ectopic miR-508-3p expression promotes proliferation and migration of pulmonary artery smooth muscle cell (PASMC). Bioinformatic, dual-luciferase assay showed NR4A3 represents directly targeted gene of miR-508-3p. Mechanistically, we demonstrated that down-regulation of miR-508-3p advances PASMC proliferation and migration via inducing NR4A3 to activate MAPK/ERK kinase signalling pathway. Altogether, our research provides a promising diagnosis of predictor and therapeutic avenues for patients in PAH.

Identification of novel biomarkers involved in pulmonary arterial hypertension based on multiple-microarray analysis.

Pulmonary arterial hypertension (PAH) is a life-threatening chronic cardiopulmonary disorder. However, studies providing PAH-related gene expression profiles are scarce. To identify hub genes involved in PAH, we investigate two microarray data sets from gene expression omnibus (GEO). A total of 150 differentially expressed genes (DEGs) were identified by limma package. Enriched Gene Ontology (GO) annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of DEGs mostly included mitotic nuclear division, ATPase activity, and Herpes simplex virus one infection. Ten hub genes from three significant modules were ascertained by Cytoscape (CytoHubba). Gene set enrichment analysis (GSEA) plots showed that transcription elongation factor complex was the most significantly enriched gene set positively correlated with the PAH group. At the same time, solute proton symporter activity was the most significantly enriched gene set positively correlated with the control group. Correlation analysis between hub genes suggested that SMC4, TOP2A, SMC2, KIF11, KIF23, ANLN, ARHGAP11A, SMC3, SMC6 and RAD50 may involve in the pathogenesis of PAH. Then, the miRNA-target genes regulation network was performed to unveil the underlying complex association among them. Finally, RNA extracted from monocrotaline (MCT)-induced Rat-PAH model lung artery tissues were to conduct quantitative real-time PCR (qRT-PCR) to validate these hub genes. In conclusion, our study offers new evidence for the underlying molecular mechanisms of PAH as well as attractive targets for diagnosis and treatment of PAH.

Human Milk Feeding Status of Preterm Infants in Neonatal Intensive Care Units in China.

BACKGROUND: Previous low human milk feeding rates in Chinese neonatal intensive care units of preterm infants were reported. There are no nationwide data on these. RESEARCH AIMS: To investigate the current status of human milk feeding for preterm infants in Chinese units and provide baseline data for future research. METHODS: A secondary data analysis was conducted from a previously established clinical database including 25 Chinese neonatal intensive care units. All infants born <34 weeks gestation and admitted to participating units from May 2015 to April 2018 were enrolled. Variables analyzed were infant data collected and the human milk feeding practices at participating units were surveyed. RESULTS: A total of 24,113 infants were included. The overall and exclusive human milk feeding rates were 58.2% and 18.8%, respectively, which increased significantly during study years. We found that rates of human milk feeding decreased with increase in gestational age and birth weight. There was significant variation in human milk feeding rates among units. Most participating Chinese neonatal intensive care units have taken measures to improve the rates of human milk feeding. CONCLUSIONS: The human milk feeding rates in Chinese neonatal intensive care units have continued to increase in the past 3 years, but there was significant variation among them. More efforts are needed to further increase the human milk feeding rates in China. TRIAL REGISTRATION: This study was registered NCT02600195 with clinicaltrials.gov on November 9, 2015.

[Analgesic effect of fentanyl in neonates during mechanical ventilation].

OBJECTIVE: To study the analgesic effect and safety of fentanyl in neonates receiving mechanical ventilation. METHODS: Thirty neonates receiving mechanical ventilation between December 2010 and February 2011 were randomized into drug intervention group and control group (n=15 each). In addition to the conventional treatment for both groups, the drug intervention group received fentanyl as the analgesic treatment. Heart rate, respiratory rate, blood pressure changes, and premature infant pain profile (PIPP) score before treatment and at 30 minutes, 2 hours, and 4 hours after treatment were recorded in both groups. Follow-up visits were performed for these infants after discharge, and the CDCC intellectual development scale for infants was applied to measure mental development index (MDI) and psychomotor development index (PDI) at 3, 6, 9, and 12 months of age. RESULTS: The respiratory rate and heart rate decreased in the drug intervention group after fentanyl treatment compared with the control group (P<0.05), and the PIPP scores in the drug intervention group was significantly lower than in the control group (P<0.05). The results of follow-up visits showed no significant differences in MDI and PDI at 3, 6, 9 and 12 months of age between the drug intervention and control groups (P>0.05). CONCLUSIONS: Fentanyl can relieve the pain response in neonates receiving mechanical ventilation, with no long-term adverse effects on neurodevelopment.

Direct calorimetric measurement of grain boundary and surface enthalpies in yttria-stabilized zirconia.

We measured the change in enthalpy with grain size of a dense nanograined yttria-stabilized zirconia by oxide melt solution calorimetry and derived a grain boundary enthalpy, 0.73 +/- 0.19 J m(-2). Surface enthalpies of nanopowders are 2.21 +/- 0.14 J m(-2) (anhydrous surface) and 1.60 +/- 0.09 J m(-2) (hydrous surface). The grain boundary enthalpy is about a factor of two smaller than the enthalpy of the anhydrous surface, suggesting that densification which maintains nanosized grains is indeed thermodynamically driven. This is the first direct calorimetric measurement of grain boundary enthalpy in a ceramic.