Methods of Gastric Tube Placement Verification in Neonates, Infants, and Children: A Systematic Review and Meta-Analysis.

INTRODUCTION: The objective was to evaluate diagnostic performance of multiple methods used to assess gastric tube placement verification in neonates, infants, and children. METHODS: A systematic review using the methods outlined in the Cochrane Handbook for Reviews of Diagnostic Test Accuracy was conducted. Eight databases were searched. Studies on neonates, infants, and children in which researchers compared different methods for gastric tube placement verification with x-ray reference standard were eligible in the review. RESULTS: Eight studies involving 911 participants that evaluated 9 index tests for gastric tube placement verification were included. Most studies were of moderate methodological quality, and most index tests were assessed in small individual studies. pH testing with cutoff values ≤ 6 for gastric tube position confirmation was the only index test subjected to meta-analysis, with the summary sensitivity and specificity being 0.77 (95% confidence interval [CI] 0.56-0.90) and 0.42 (95% CI 0.16-0.73). Other tests for gastric tube placement verification showed great variations in sensitivities and specificities. DISCUSSION: pH ≤ 6 is not sufficiently accurate to be recommended for gastric tube placement verification in neonates, infants, and children. Diagnostic performance of pH ≤ 4 or 5 and other methods cannot be determined because of the paucity of data and methodological variations in studies. Clinical practice related to the diagnostic tests used will continue to be dictated by local preferences and cost factors, until stronger evidence becomes available.

Microwave-Assisted Synthesis of Imidazo[4,5-f][1,10]phenanthroline Derivatives as Apoptosis Inducers in Chemotherapy by Stabilizing Bcl-2 G-quadruplex DNA.

Herein, a series of imidazo[4,5-f][1,10] phenanthroline derivatives RPIP (PIP = imidazo [4,5-f][1,10] phenanthroline, R = NO2, 1; CF3, 2; Cl, 3; OH, 4) have been synthesized in yields of 82.3-94.7% at 100 °C under the irradiation of microwave. MTT assay has been utilized to evaluate the inhibitory activity (IC50) of these compounds against the growth of various tumor cells, and the results revealed that these compounds, especially 1, exhibited excellent inhibitory activity against the growth of A549 cells with IC50 of 15.03 µM. Moreover, it's also confirmed that 1 can penetrate into the membrane of tumor cells and distribute in mitochondria when observed under microscopy, resulting apoptosis of tumor cells. The further studies showed that 1 can bind to bcl-2 G-quadruplex DNA, which demonstrated by the increase of melting point of bcl-2 G4 DNA in the presence of 1, as well as electronic titration and emission spectra. In a word, this kind of compound may develop as a potential apoptosis inducer in cancer chemotherapy via binding and stabilizing to the bcl-2 G-quadruplex DNA.