Lung ultrasound score as a predictor of ventilator use in preterm infants with dyspnea within 24 h after dhospitalization.

BACKGROUND: Selecting the correct ventilation strategy is crucial for the survival of preterm infants with dyspnea in NICU. Lung ultrasound score (LUSsc) is a potential predictor for respiratory support patterns in preterm infants. METHODS: We prospectively included 857 preterm infants. LUS was performed in the first 2 h after admission, and LUSsc was determined by two specialist sonographers. Participants were divided into two categories according to gestational age (<32+0 weeks and 32+0-36+6 weeks) and randomly divided into a training set and a validation set. There were two main outcomes: invasive and non-invasive respiratory support. In the training set, clinical factors were analyzed to find the best cut-off value of LUSsc, and consistency was verified in the verification set. The choice of invasive respiratory support was based on neonatal mechanical ventilation strategies. RESULTS: Preterm infants with invasive respiratory support had a higher LUSsc, greater use of Pulmonary Surfactant（PS）, and lower Oxygenation Index（OI）、birth weight than those with non-invasive support. In the <32+0 weeks group, the area under the curve (AUC) for the receiver operating characteristic curve plotted with 2-h LUSsc was 0.749 (95% CI: 0.689-0.809), the cut-off point of LUSsc was 8, and the sensitivity and specificity were 74.0% and 68.3%, respectively. In the 32+0-36+6 weeks group, the AUC was 0.863 (95% CI: 0.811-0.911), with a cut-off point of 7. Sensitivity and specificity were 75.3% and 0.836%, respectively. In the validation set, using the actual clinical respiratory support selection results for verification, the validation results showed for the <32+0 weeks group (Kappa value 0.660, P < 0.05, McNemar test P > 0.05) for preterm 32+0-36+6 weeks (Kappa value 0.779, P < 0.05, McNemar test P > 0.05). CONCLUSION: The LUSsc showed good reliability in predicting respiratory support mode for preterm infants with dyspnea. Registered at ClinicalTrials.gov (identifier: chiCTR1900023869).

Synergistic remineralization of enamel white spot lesions using mesoporous bioactive glasses loaded with amorphous calcium phosphate.

Objectives: The purpose of this study was to create a new delivery system that can synergistically remineralize enamel white spot lesions (WSLs). Materials and methods: The delivery system (PAA-ACP@aMBG) was prepared by using aminated mesoporous bioactive glasses (aMBG) as the carrier loaded with polyacrylic-stabilized amorphous calcium phosphate (PAA-ACP). The materials were characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), inductively coupled plasma-optical emission spectrometry (ICP-OES), and so on. Forty-eight artificial WSLs enamel samples were randomized to four groups: artificial saliva (negative control, NC), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), PAA-ACP@aMBG, and MBG. The effects of demineralization and remineralization of the enamel surface were compared by means of surface microhardness (SMH) measurements, surface color change measurements, fluorescence microscopy (FM), X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Results: There was no significant difference in the surface microhardness recovery rate (SMHRR) or color recovery rate (CRR) among the CPP-ACP group, PAA-ACP@aMBG group and MBG group (P>0.05), but these values were significantly higher than those in the NC group (p < 0.01). FM demonstrated that the remineralization depth in the PAA-ACP@aMBG group was significantly greater than that of the remaining three groups (p < 0.01). SEM analysis indicated that the enamel demineralization marks in the PAA-ACP@aMBG group, CPP-ACP group, and MBG group were obscured by mineral deposition. Conclusions: PAA-ACP@aMBG showed good mineralization properties, implying its great potential for clinical application.

[Reference ranges of platelet and related parameters within 24 hours after birth in preterm infants with different gestational ages].

OBJECTIVE: To study the reference ranges of platelet and related parameters within 24 hours after birth in preterm infants with different gestational ages. METHODS: According to the inclusion and exclusion criteria, a retrospective analysis was performed for the chart review data of 1 070 preterm infants with a gestational age of 23-36+6 weeks who were admitted to the neonatal intensive care unit from January to December in 2018. The reference ranges of platelet parameters were calculated for the preterm infants within 24 hours after birth. RESULTS: There were no significant differences in platelet count (PLT) and plateletcrit (PCT) among the preterm infants with different gestational ages (P>0.05). The late preterm infants (34-36+6 weeks; n=667) had significantly lower mean platelet volume (MPV) and platelet distribution width (PDW) than the extremely preterm infants (23-27+6 weeks; n=36) and the early preterm infants (28-33+6 weeks; n=367) (P<0.05). There were no significant differences in these platelet parameters between the preterm infants with different sexes (P>0.05). The reference ranges of platelet parameters in preterm infants were calculated based on gestational age. The reference ranges of PLT and PCT were (92-376)×109/L and 0.1%-0.394% respectively, for the preterm infants with a gestational age of 23-36+6 weeks. The reference ranges of MPV and PDW were 9.208-12.172 fl and 8.390%-16.407% respectively, for the preterm infants with a gestational age of 23-36+6 weeks; the reference ranges of MPV and PDW were 9.19-11.95 fl and 9.046%-15.116% respectively, for the preterm infants with a gestational age of 34-36+6 weeks. CONCLUSIONS: The MPV and PDW of preterm infants with different gestational age are different within 24 hours after birth, and it is more helpful for clinical practice to formulate the reference range of MPV and PDW according to gestational age.