RESUMO
Airway stent insertion is important for patients with airway stenosis. Currently, the most widely used airway stents in clinical procedures are silicone and metallic stents, which offer patients effective treatment. However, these stents composed of permanent materials need to be removed, subjecting patients to invasive manipulation once more. As a result, there is a growing demand for biodegradable airway stents. Biodegradable materials for airway stents are now available in two types: biodegradable polymers and biodegradable alloys. Polymers that include poly (
Assuntos
Polidioxanona , Traqueia , Animais , Humanos , Polímeros , Stents , Ligas , Implantes AbsorvíveisRESUMO
Lipid nanoparticles (LNPs) have demonstrated efficacy and safety for mRNA vaccine administration by intramuscular injection; however, the pulmonary delivery of mRNA encapsulated LNPs remains challenging. The atomization process of LNPs will cause shear stress due to dispersed air, air jets, ultrasonication, vibrating mesh etc., leading to the agglomeration or leakage of LNPs, which can be detrimental to transcellular transport and endosomal escape. In this study, the LNP formulation, atomization methods and buffer system were optimized to maintain the LNP stability and mRNA efficiency during the atomization process. Firstly, a suitable LNP formulation for atomization was optimized based on the in vitro results, and the optimized LNP formulation was AX4, DSPC, cholesterol and DMG-PEG2K at a 35/16/46.5/2.5 (%) molar ratio. Subsequently, different atomization methods were compared to find the most suitable method to deliver mRNA-LNP solution. Soft mist inhaler (SMI) was found to be the best for pulmonary delivery of mRNA encapsulated LNPs. The physico-chemical properties such as size and entrapment efficiency (EE) of the LNPs were further improved by adjusting the buffer system with trehalose. Lastly, the in vivo fluorescence imaging of mice demonstrated that SMI with proper LNPs design and buffer system hold promise for inhaled mRNA-LNP therapies.
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Lipídeos , Nanopartículas , Camundongos , Animais , Lipídeos/química , RNA Mensageiro , Lipossomos , Endossomos , Nanopartículas/química , RNA Interferente PequenoRESUMO
Presented here are two water stable oxalate-based coordination polymers with in situ generated cyclic dipeptides, namely, (C12H16N6O2)[Zn2(C2O4)3] (SCU-63) and Mn(C2O4)(C12H14N6O2) (SCU-66). SCU-63 has a honeycomb-like layer intercalated with protonated cyclic dipeptide cations. SCU-66 has a diamondoid framework containing cyclic dipeptide ligands. The two compounds show high proton conductivity on the order of 10-3 S cm-1 at 85 °C under 98% relative humidity.
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Dipeptídeos/química , Oxalatos/química , Peptídeos Cíclicos/química , Polímeros/química , Prótons , Água/química , Histidina/química , Modelos Moleculares , Conformação MolecularRESUMO
This paper presents a microfluidic planar patch clamp system based on a hydrophilic polymer poly(ethylene glycol) diacrylate (PEGDA) for whole cell current recording. The whole chip is fabricated by UV-assisted molding method for both microfluidic channel structure and planar electrode partition. This hydrophilic patch clamp chip has demonstrated a relatively high gigaseal success rate of 44% without surface modification compared with PDMS based patch clamp devices. This chip also shows a capability of rapid intracellular and extracellular solution exchange with high stability of gigaseals. The capillary flow kinetic experiments demonstrate that the flow rates of PEGDA microfluidic channels are around two orders of magnitude greater than those for PDMS-glass channels with the same channel dimensions. This hydrophilic polymer based patch clamp chips have significant advantages over current PDMS elastomer based systems such as no need for surface modification, much higher success rate of cell gigaseals and rapid solution exchange with stable cell gigaseals. Our results indicate the potential of these devices to serve as useful tools for pharmaceutical screening and biosensing tasks.