Clinical course in infants diagnosed with transient tachypnea of newborn: A clinical trial assessing the role of conservative versus conventional management.

BACKGROUND: Transient tachypnea of the newborn (TTN) is a respiratory disorder secondary to inadequate or delayed clearance of lung fluids. Early symptoms of the disease are indistinguishable from neonatal respiratory distress syndrome, pneumonia, and persistent pulmonary hypertension. Therefore, these newborns, in addition to receiving conservative management, receive antibiotics until blood cultures provide definite results. In this study, we assessed the clinical course of neonates diagnosed with TTN who received conventional versus conservative management. METHODS: One hundred and thirty neonates diagnosed as having TTN were randomly enrolled in two study groups. While patients belonging to one group received conservative management, those from the other group were treated with conventional medical therapy. RESULTS: Mean duration of hospitalization was 7 ± 0.2 in the conventional and 5 ± 1.5 in the conservative group. Duration of antibiotic therapy was 6.7 ± 2.47 days in the conventional group. CONCLUSION: Newborns diagnosed with TTN without prenatal risk factors and a negative C reactive protein test do not need to be administered antibiotics and hospitalized until confirmatory blood culture results are obtained.

Ultra-high-density 3D DNA arrays within nanoporous biocompatible membranes for single-molecule-level detection and purification of circulating nucleic acids.

Extracellular nucleic acids freely circulating in blood and other physiologic fluids are important biomarkers for non-invasive diagnostics and early detection of cancer and other diseases, yet difficult to detect because they exist in very low concentrations and large volumes. Here we demonstrate a new broad-range sensor platform for ultrasensitive and selective detection of circulating DNA down to the single-molecule level. The biosensor is based on a chemically functionalized nanoporous diamond-like carbon (DLC) coated alumina membrane. The few nanometer-thick, yet perfect and continuous DLC-coating confers the chemical stability and biocompatibility of the sensor, allowing its direct application in biological conditions. The selective detection is based on complementary hybridization of a fluorescently-tagged circulating cancer oncomarker (a 21-mer nucleic acid) with covalently immobilized DNA on the surface of the membrane. The captured DNAs are detected in the nanoporous structure of the sensor using confocal scanning laser microscopy. The flow-through membrane sensor demonstrates broad-range sensitivity, spanning from 10(15) molecules per cm(2) down to single molecules, which is several orders of magnitude improvement compared to the flat DNA microarrays. Our study suggests that these flow-through type nanoporous sensors represent a new powerful platform for large volume sampling and ultrasensitive detection of different chemical biomarkers.

Surface charge effects in protein adsorption on nanodiamonds.

Understanding the interaction of proteins with charged diamond nanoparticles is of fundamental importance for diverse biomedical applications. Here we present a thorough study of protein binding, adsorption kinetics and structure on strongly positively (hydrogen-terminated) and negatively (oxygen-terminated) charged nanodiamond particles using a quartz crystal microbalance by dissipation and infrared spectroscopy. By using two model proteins (bovine serum albumin and lysozyme) of different properties (charge, molecular weight and rigidity), the main driving mechanism responsible for the protein binding to the charged nanoparticles was identified. Electrostatic interactions were found to dominate the protein adsorption dynamics, attachment and conformation. We developed a simple electrostatic model that can qualitatively explain the observed adsorption behaviour based on charge-induced pH modifications near the charged nanoparticle surfaces. Under neutral conditions, the local pH around the positively and negatively charged nanodiamonds becomes very high (11-12) and low (1-3) respectively, which has a profound impact on the protein charge, hydration and affinity to the nanodiamonds. Small proteins (lysozyme) were found to form multilayers with significant conformational changes to screen the surface charge, while larger proteins (albumin) formed monolayers with minor conformational changes. The findings of this study provide a step forward toward understanding and eventually predicting nanoparticle interactions with biofluids.