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1.
Research (Wash D C) ; 6: 0023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37040478

RESUMEN

Achieving rapid shedding of droplets from solid surfaces has received substantial attention because of its diverse applications. Previous studies have focused on minimizing contact times of liquid droplets interacting with stationary surfaces, yet little consideration has been given to that of moving surfaces. Here, we report a different scenario: A water droplet rapidly detaches from micro/nanotextured rotating surfaces in an intriguing doughnut shape, contributing to about 40% contact time reduction compared with that on stationary surfaces. The doughnut-shaped bouncing droplet fragments into satellites and spontaneously scatters, thus avoiding further collision with the substrate. In particular, the contact time is highly dependent on impact velocities of droplets, beyond previous descriptions of classical inertial-capillary scaling law. Our results not only deepen the fundamental understanding of droplet dynamics on moving surfaces but also suggest a synergistic mechanism to actively regulate the contact time by coupling the kinematics of droplet impingement and surface rotation.

2.
Pharmaceutics ; 14(6)2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35745796

RESUMEN

The multi-inlet vortex mixer (MIVM) has emerged as a novel bottom-up technology for solid nanoparticle preparation. However, its performance in liposome preparation remains unknown. Here, two key process parameters (aqueous/organic flow rate ratio (FRR) and total flow rate (TFR)) of MIVM were investigated for liposome preparation. For this study, two model drugs (lysozyme and erythromycin) were chosen for liposome encapsulation as the representative hydrophilic and hydrophobic drugs, respectively. In addition, two modified MIVMs, one with herringbone-patterned straight inlets and one with zigzag inlets, were designed to further improve the mixing efficiency, aiming to achieve better drug encapsulation. Data showed that FRR played an important role in liposome size control, and a size of <200 nm was achieved by FRR higher than 3:1. Moreover, increasing TFR (from 1 to 100 mL/min) could further decrease the size at a given FRR. However, similar regularities in controlling the encapsulation efficiency (EE%) were only noted in erythromycin-loaded liposomes. Modified MIVMs improved the EE% of lysozyme-loaded liposomes by 2~3 times at TFR = 40 mL/min and FRR = 3:1, which was consistent with computational fluid dynamics simulations. In summary, the good performance of MIVM in the control of particle size and EE% makes it a promising tool for liposome preparation, especially for hydrophobic drug loading, at flexible production scales.

3.
Pharmaceutics ; 13(2)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33535512

RESUMEN

Dry powder inhaler (DPI) is a device used to deliver a drug in dry powder form to the lungs. A wide range of DPI products is currently available, with the choice of DPI device largely depending on the dose, dosing frequency and powder properties of formulations. Computational fluid dynamics (CFD), together with various particle motion modelling tools, such as discrete particle methods (DPM) and discrete element methods (DEM), have been increasingly used to optimise DPI design by revealing the details of flow patterns, particle trajectories, de-agglomerations and depositions within the device and the delivery paths. This review article focuses on the development of the modelling methodologies of flow and particle behaviours in DPI devices and their applications to device design in several emerging fields. Various modelling methods, including the most recent multi-scale approaches, are covered and the latest simulation studies of different devices are summarised and critically assessed. The potential and effectiveness of the modelling tools in optimising designs of emerging DPI devices are specifically discussed, such as those with the features of high-dose, pediatric patient compatibility and independency of patients' inhalation manoeuvres. Lastly, we summarise the challenges that remain to be addressed in DPI-related fluid and particle modelling and provide our thoughts on future research direction in this field.

5.
Neuropsychiatr Dis Treat ; 14: 2697-2701, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30349268

RESUMEN

The pathophysiology of schizophrenia may involve increased production of inflammatory cytokines by activated microglia. Minocycline can inhibit activated microglia and may improve secondary negative symptoms and/or cognitive functions when used as adjuvant to antipsychotics. Effects on minocycline on primary and enduring negative symptoms in deficit schizophrenia (DS) are unknown. We present a male patient with a 3-year history of DS. He was treated for 12 weeks with risperidone at a maximal dose of 6 mg per day, then for 10 weeks with olanzapine at 20 mg per day. Symptoms did not improve, and body mass index increased from 20.41 to 22.84 kg/m2. Serum levels of several inflammatory cytokines were elevated, so we prescribed minocycline as adjunct to aripiprazole for 12 weeks. Negative symptoms and cognitive impairment improved, and serum levels of inflammatory cytokines decreased. Our case suggests that clinicians may consider minocycline as adjunct therapy to antipsychotics in patients with DS with elevated serum levels of inflammatory cytokines. This highlights the need for further research into possible relationships of minocycline with negative symptoms and cognitive function in patients with DS.

7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1639, 2009 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-21578654

RESUMEN

In the title compound, (C(22)H(23)N(2))[Hg(2)I(6)](0.5)·(CH(3))(2)SO, the 1-butyl-3-(1-naphthyl-meth-yl)benzimidazolium anion lies across a centre of inversion. The dihedral angle between the benzimidazolium and naphthalene ring systems is 81.9 (3)°. In the crystal structure, π-π stacking inter-actions are observed between the imidazolium ring and the unsubstituted benzene ring of the naphthalene ring system, with a centroid-centroid separation of 3.510 (5) Å. In the centrosymmetric anion, the Hg(II) atoms are in a distorted tetrahedral coordination. The dimethyl sulfoxide solvent mol-ecule is disordered over two sites with occupancies of 0.615 (9) and 0.385 (9).

8.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1652, 2009 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-21578664

RESUMEN

In the title compound, (C(11)H(15)N(2))(2)[HgBr(4)], the tetra-coordinated Hg(II) center of the complex anion adopts a distorted tetra-hedral geometry [Hg-Br = 2.5755 (8)-2.623 (11) Šand Br-Hg-Br = 103.78 (19)-116.4 (3)°]. One of the Br atoms is disordered over two sites [site-occupancy factors = 0.51 (6) and 0.49 (6)]. The N-C-N angles in the cations are 110.7 (6) and 111.4 (7)°. In the crystal packing, a supra-molecular chain is formed via both weak inter-molecular C-H⋯Br hydrogen bonds and π-π aromatic ring stacking inter-actions [centroid-centroid separation = 3.803 (1) Å].

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o478, 2008 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-21201503

RESUMEN

In the title compound, C(10)H(11)N(2) (+)·PF(6) (-)·C(10)H(10)N(2), the H atom involved in protonation is disordered equally between the cation and the neutral mol-ecule. The dihedral angle between the phenyl and imidazole rings is 82.6 (2)°. In the crystal structure, there are head-to-tail π-π stacking inter-actions between imidazole rings; the inter-planar separation is 3.295 (1) Šand the centroid-centroid separation is 3.448 (3) Å. In the centrosymmetric anion, two F atoms are disordered over two positions; the refined site-occupancy factors are 0.855 (11) and 0.145 (11).

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