The effect of high flow nasal oxygen therapy in intensive care units: a systematic review and meta-analysis.

BACKGROUND: High flow nasal oxygen (HFNO) therapy has been widely used in intensive care units (ICU); however, its efficacy remains inconclusive. This systematic review and meta-analysis aimed to compare the efficacy of HFNO therapy with th at of alternative noninvasive oxygen therapies such as conventional oxygen therapy (COT) and noninvasive ventilation (NIV) in ICU. METHODS: A Pubmed, Embase, Web of Science, Cochrane Library database search was performed in March 2020. Results: The meta-analysis ultimately included 17 clinical studies. Compared with the overall effect of COT and NIV, HFNO was associated with a low incidence of pneumonia (95% CI: 0.6-0.99, P = 0.04) and improvement in lowest pulse oxygen saturation (SpO2) during oxygenation (95% CI: 0.02-1.61; P = 0.04). However, no differences were detected in the following outcomes: length of ICU stay, the rate of intubation or reintubation, mortality at day 28, hospital mortality, and SpO2 at the end of oxygen therapy (all P > 0.05). CONCLUSIONS: In adult patients in ICU, HFNO may improve oxygenation and decrease pneumonia rate without affecting the length of ICU stay, intubation or reintubation rate, mortality, and SpO2 at the end of oxygen therapy.

Multilayered inorganic-organic microdisks as ideal carriers for high magnetothermal actuation: assembling ferrimagnetic nanoparticles devoid of dipolar interactions.

The two major limitations for nanoparticle based magnetic hyperthermia in theranostics are the delivery of a sufficient number of magnetic nanoparticles (MNPs) with high heating power to specific target cells and the residence time of the MNPs at the target location. Ferromagnetic or Ferrimagnetic single domain nanoparticles (F-MNPs), with a permanent magnetic dipole, produce larger magnetic and thermal responses than superparamagnetic nanoparticles (SP-MNPs) but also agglomerate more. MNP agglomeration degrades their heating potential due to dipolar interaction effects and interferes with specific targeting. Additionally, MNPs bound to cells are often endocytosed by the cells or, in vivo, cleared out by the immune system via uptake in macrophages. Here, we present a versatile approach to engineer inorganic-polymeric microdisks, loaded with biomolecules, fluorophores and Fe3O4 F-MNPs that solves both challenges. These microdisks deliver the F-MNPs efficiently, while controlling any undesirable agglomeration and dipolar interaction, while also rendering the F-MNPs endocytosis resistant. We show that these micro-devices are suitable carriers to transport a flat assembly of F-MNPs to the cell membrane unchanged, preserving the magnetic response of the MNPs in any biological environment. The F-MNPs concentration per microdisk and degree of MNP interaction are tunable. We demonstrate that the local heat generated in microdisks is proportional to the surface density of F-MNPs when attached to the cell membrane. The key innovation in the production of these microdisks is the fabrication of a mushroom-shaped photolithographic template that enables easy assembly of the inorganic film, polymeric multilayers, and MNP cargo while permitting highly efficient lift-off of the completed microdisks. During the harvesting of the flat microdisks, the supporting mushroom-shaped templates are sacrificed. These resulting magnetic hybrid microdisks are tunable and efficient devices for magnetothermal actuation and hyperthermia.

Self-Junctioned Copper Nanofiber Transparent Flexible Conducting Film via Electrospinning and Electroplating.

Self-junctioned copper nanofiber transparent flexible films are produced using electrospinning and electroplating processes that provide high performances of T = 97% and Rs = 0.42 Ω sq(-1) by eliminating junction resistance at wire intersections. The film remains conductive after being stretched by up to 770% (films with T = 76%) and after 1000 cycles of bending to a 5 mm radius.

Controlled Growth of a Hierarchical Nickel Carbide "Dandelion" Nanostructure.

We present a new type of highly hierarchical but nonporous nanostructure with a unique "dandelion" morphology. Based on the time evolution of these Ni3 C nanostructures, we suggest a mechanism for their formation. This type of hierarchical nanocrystal, with high accessible specific surface area in a relatively large (ca. 750 nm overall diameter) stable structure, can be valuable in catalysis and related applications.

Rapid Light-Triggered Drug Release in Liposomes Containing Small Amounts of Unsaturated and Porphyrin-Phospholipids.

Prompt membrane permeabilization is a requisite for liposomes designed for local stimuli-induced intravascular release of therapeutic payloads. Incorporation of a small amount (i.e., 5 molar percent) of an unsaturated phospholipid, such as dioleoylphosphatidylcholine (DOPC), accelerates near infrared (NIR) light-triggered doxorubicin release in porphyrin-phospholipid (PoP) liposomes by an order of magnitude. In physiological conditions in vitro, the loaded drug can be released in a minute under NIR irradiation, while liposomes maintain serum stability otherwise. This enables rapid laser-induced drug release using remarkably low amounts of PoP (i.e., 0.3 molar percent). Light-triggered drug release occurs concomitantly with DOPC and cholesterol oxidation, as detected by mass spectrometry. In the presence of an oxygen scavenger or an antioxidant, light-triggered drug release is inhibited, suggesting that the mechanism is related to singlet oxygen mediated oxidization of unsaturated lipids. Despite the irreversible modification of lipid composition, DOPC-containing PoP liposome permeabilization is transient. Human pancreatic xenograft growth in mice is significantly delayed with a single chemophototherapy treatment following intravenous administration of 6 mg kg(-1) doxorubicin, loaded in liposomes containing small amounts of DOPC and PoP.

Ferroelastic domain organization and precursor control of size in solution-grown hafnium dioxide nanorods.

We demonstrate that the degree of branching of the alkyl (R) chain in a Hf(OR)4 precursor allows for control over the length of HfO2 nanocrystals grown by homocondensation of the metal alkoxide with a metal halide. An extended nonhydrolytic sol-gel synthesis has been developed that enables the growth of high aspect ratio monoclinic HfO2 nanorods that grow along the [100] direction. The solution-grown elongated HfO2 nanorods show remarkable organization of twin domains separated by (100) coherent twin boundaries along the length of the nanowires in a morphology reminiscent of shape memory alloys. The sequence of finely structured twin domains each spanning only a few lattice planes originates from the Martensitic transformation of the nanorods from a tetragonal to a monoclinic structure upon cooling. Such ferroelastic domain organization is uncharacteristic of metal oxides and has not thus far been observed in bulk HfO2. The morphologies observed here suggest that, upon scaling to nanometer-sized dimensions, HfO2 might exhibit mechanical properties entirely distinctive from the bulk.

How amelogenin orchestrates the organization of hierarchical elongated microstructures of apatite.

Amelogenin (Amel) accelerates the nucleation of hydroxyapatite (HAP) in supersaturated solutions of calcium phosphate (Ca-P), shortening the induction time (delay period), under near-physiological conditions of pH, temperature, and ionic strength. Hierarchically organized Amel and amorphous calcium phosphate (ACP) nanorod microstructures are formed involving a coassembly of Amel-ACP particles at low supersaturations and low protein concentrations in a slow, well-controlled, constant composition (CC) crystallization system. At the earliest nucleation stages, the CC method allows the capture of prenucleation clusters and intermediate nanoclusers, spherical nanoparticles, and nanochains prior to enamel-like nanorod microstructure formations at later maturation stages. Amel-ACP nanoscaled building blocks are formed spontaneously by synergistic interactions between flexible Amel protein molecules and Ca-P prenucleation clusters, and these spherical nanoparticles evolve by orientated aggregation to form nanochains. Our results suggest that, in vivo, Amel may determine the structure of enamel by controlling prenucleation cluster aggregation at the earliest stages by forming stable Amel-ACP microstructures prior to subsequent crystal growth and mineral maturation.