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Scientific Reports Dec 2023The Patient Preference Survey aims to understand unmet needs related to riluzole management in people with Amyotrophic Lateral Sclerosis (ALS) and to identify which...
The Patient Preference Survey aims to understand unmet needs related to riluzole management in people with Amyotrophic Lateral Sclerosis (ALS) and to identify which characteristics of a new formulation could better match their preferences. The survey involved 117 people with ALS (PALS) treated with riluzole in four European countries. The dysphagic PALS were least satisfied with the riluzole tablet and oral suspension and with ease in self-administration; up to 68% of respondents postponed or missed the treatment due to swallowing difficulties and need of caregiver assistance. Overall, 51% of tablet and 53% of oral suspension users regularly crushed or mixed riluzole with beverages, respectively; PALS who always manipulated riluzole showed low satisfaction with the formulation and considered the risk of choking and pneumonia the most worrisome event. The survey evaluated the driving factors in choosing/switching the therapy: 67% of PALS declared a low risk of choking. The research finally evaluated which attributes of a new formulation would be preferred: the most relevant were ease of use (4.3/5), convenient/portable packaging (4.0/5) and oral-dissolving properties without tongue motility (3.9/5). The Patient Preference Survey suggests that patients have several unmet needs and preferences that could be addressed by a different formulation, e.g. using oral film technologies.
Topics: Humans; Riluzole; Amyotrophic Lateral Sclerosis; Suspensions; Europe; Airway Obstruction; Tablets; Neuroprotective Agents
PubMed: 38110502
DOI: 10.1038/s41598-023-49424-3 -
Sensors (Basel, Switzerland) Aug 2022Cellulose, the most abundant sustainable material on Earth, has excellent mechanical and physical properties, high optical transparency, biocompatibility, and...
Cellulose, the most abundant sustainable material on Earth, has excellent mechanical and physical properties, high optical transparency, biocompatibility, and piezoelectricity. So, it has many possibilities for future materials, and many researchers are interested in its application. In this paper, cellulose nanofiber (CNF) and CNF/polyvinyl alcohol (PVA) films are made, and their vibration energy harvesting is studied. CNF was isolated by chemical and physical methods, and the CNF suspension was cast on a flat substrate to make a film. A cast CNF wet film stayed in a 5 Tesla superconductor magnet for 7 days, which resulted in CNF alignment perpendicular to the magnetic field. To further improve the mechanical properties of the CNF film, mechanical stretching was applied. The CNF suspension was mixed with PVA, giving the film toughness. The cast CNF/PVA wet film was mechanically stretched and dried, which improved the CNF alignment. The fabricated CNF and CNF/PVA films were characterized using scanning electron microscopy and X-ray diffraction to verify the alignment. By stretching, the aligned CNF/PVA film exhibits the largest mechanical properties along the aligned direction. The maximum Young's modulus and tensile strength of the 50% stretched CNF/PVA film are 14.9 GPa and 170.6 MPa, respectively. Finally, a vibration energy harvesting experiment was performed by invoking the piezoelectric behavior of the pure CNF, and 50% stretched CNF/PVA films. The harvester structure was innovated by adopting a cymbal structure, which was beneficial to producing large in-plane strain on the films. The designed cymbal structure was analyzed using ANSYS, and its natural frequency was experimentally verified. The CNF/PVA film performs better vibration energy harvesting than the pure CNF film. The CNF/PVA film is applicable for biocompatible and flexible vibration energy harvesting.
Topics: Cellulose; Nanofibers; Polyvinyl Alcohol; Suspensions; Tensile Strength; Vibration
PubMed: 36016041
DOI: 10.3390/s22166280 -
Proceedings of the National Academy of... Nov 2022Debris flows are dense and fast-moving complex suspensions of soil and water that threaten lives and infrastructure. Assessing the hazard potential of debris flows...
Debris flows are dense and fast-moving complex suspensions of soil and water that threaten lives and infrastructure. Assessing the hazard potential of debris flows requires predicting yield and flow behavior. Reported measurements of rheology for debris flow slurries are highly variable and sometimes contradictory due to heterogeneity in particle composition and volume fraction ([Formula: see text]) and also inconsistent measurement methods. Here we examine the composition and flow behavior of source materials that formed the postwildfire debris flows in Montecito, CA, in 2018, for a wide range of [Formula: see text] that encapsulates debris flow formation by overland flow. We find that shear viscosity and yield stress are controlled by the distance from jamming, [Formula: see text], where the jamming fraction [Formula: see text] is a material parameter that depends on grain size polydispersity and friction. By rescaling shear and viscous stresses to account for these effects, the data collapse onto a simple nondimensional flow curve indicative of a Bingham plastic (viscoplastic) fluid. Given the highly nonlinear dependence of rheology on [Formula: see text], our findings suggest that determining the jamming fraction for natural materials will significantly improve flow models for geophysical suspensions such as hyperconcentrated flows and debris flows.
Topics: Suspensions; Rheology; Soil; Water; Plastics
PubMed: 36279442
DOI: 10.1073/pnas.2209109119 -
International Journal of Nanomedicine 2024Nanosuspensions have garnered recent attention as a promising strategy for mitigating the bioavailability challenges of hydrophobic drugs, particularly those... (Review)
Review
Nanosuspensions have garnered recent attention as a promising strategy for mitigating the bioavailability challenges of hydrophobic drugs, particularly those characterized by poor solubility in both aqueous and organic environments. Addressing solubility issues associated with poorly water-soluble drugs has largely resolved the need to enhance drug absorption and bioavailability. As mucosal formulations and topical administration progress in the future, nanosuspension drug delivery, straightforward formulation techniques, and versatile applications will continue to be subjects of interest. Nanosuspensions have undergone extensive scrutiny in preparation for topical applications, encompassing ocular, pulmonary, and dermal usage. Among the numerous methods aimed at improving cutaneous application, nanocrystals represent a relatively recent yet profoundly intriguing approach. Despite the increasing availability of various nanosuspension products, primarily designed for oral administration, only a limited number of studies have explored skin permeability and drug accumulation in the context of nanosuspensions. Nevertheless, the scant published research unequivocally underscores the potential of this approach for enhancing cutaneous bioavailability, particularly for active ingredients with low to medium solubility. Nanocrystals exhibit increased skin adhesiveness in addition to heightened saturation solubility and dissolution rate, thereby augmenting cutaneous distribution. The article provides a comprehensive overview of nanosuspensions for topical application. The methodology employed is robust, with a well-defined experimental design; however, the limited sample size raises concerns about the generalizability of the findings. While the results demonstrate promising outcomes in terms of enhanced drug delivery, the discussion falls short of addressing certain limitations. Additionally, the references largely focus on recent studies, but a more diverse inclusion of historical perspectives could offer a more holistic view of the subject.
Topics: Humans; Suspensions; Drug Delivery Systems; Biological Availability; Nanoparticles; Administration, Oral; Solubility; Particle Size
PubMed: 38293608
DOI: 10.2147/IJN.S447429 -
Analytical Biochemistry Sep 2020In analytical ultracentrifugation it is often very useful to resuspend samples in situ after sedimentation experiments for further investigation. This can be achieved by...
In analytical ultracentrifugation it is often very useful to resuspend samples in situ after sedimentation experiments for further investigation. This can be achieved by manually subjecting the entire sample cell assembly to gentle motion that causes the air bubble in the sample compartment to repeatedly move through the solution and thereby cause convection. Here we describe a cell mixing device that can accomplish the same through axial rotation and slow rocking motion. This cell mixer is low-cost, open-source, and can be easily assembled from readily available components. It can efficiently mix multiple sample cells side-by-side and may be used with various centerpiece designs.
Topics: Automation, Laboratory; Serum Albumin, Bovine; Specimen Handling; Suspensions; Thyroglobulin; Ultracentrifugation
PubMed: 32407733
DOI: 10.1016/j.ab.2020.113771 -
Medical Principles and Practice :... 2021The objectives were to prepare, characterize, and evaluate different ibuprofen (IBU) nanosuspensions.
INTRODUCTION
The objectives were to prepare, characterize, and evaluate different ibuprofen (IBU) nanosuspensions.
METHODS
The nanosuspensions produced by ultrahomogenization were compared with a marketed IBU suspension for particle size, in vitro dissolution, and in vivo absorption. Five groups of rabbits were orally administered with 25 mg/kg of IBU nanosuspension, nanoparticles, unhomogenized suspension, marketed product, and untreated suspension. A sixth group received 5 mg/kg IBU intravenously. Blood samples obtained were analyzed by chromatography.
RESULTS
The nanosuspensions showed significant decrease in particle size. Polyvinylpyrrolidone (PP) K30 profoundly increased aqueous solubility of IBU. Addition of Tween 80 (TW), in equal amount as PP (IBU:PP:TW, 1:2:2 w/w), resulted in much smaller particle size and better dissolution rate. The Cmax values achieved were 14.8 ± 1.64, 11.1 ± 1.37, 9.01 ± 0.761, 7.03 ± 1.38, and 3.23 ± 1.03 μg/mL, and the tmax values were 36 ± 8.2, 39 ± 8.2, 100 ± 17.3, 112 ± 15, and 105 ± 17 min for the nanosuspension, nanoparticle, unhomogenized suspension, marketed IBU suspension, and untreated IBU suspension in water, respectively. Bioavailability of the different formulations relative to the marketed suspension was found to be in the following sequence: nanosuspension > unhomogenized suspension > nanoparticles > untreated IBU suspension.
CONCLUSION
IBU/PP/TW nanosuspension showed enhanced in vitro and in vivo performance as compared to the marketed product. Nanosuspensions prepared by the ultrahigh-pressure homogenization technique can be used as a good formulation strategy to enhance the rate and extent of absorption of poorly soluble drugs.
Topics: Animals; Biological Availability; Chromatography, High Pressure Liquid; Ibuprofen; Nanostructures; Nanotechnology; Rabbits; Solubility; Solvents; Suspensions
PubMed: 33823524
DOI: 10.1159/000516299 -
Journal of the Royal Society, Interface Jan 2022Suspension feeders (SFs) evolved a high diversity of mechanisms, sometimes with remarkably convergent morphologies, to retain plankton, detritus and man-made particles...
Suspension feeders (SFs) evolved a high diversity of mechanisms, sometimes with remarkably convergent morphologies, to retain plankton, detritus and man-made particles with particle sizes ranging from less than 1 µm to several centimetres. Based on an extensive literature review, also including the physical and technical principles of solid-liquid separation, we developed a set of 18 ecological and technical parameters to review 35 taxa of suspension-feeding Metazoa covering the diversity of morphological and functional principles. This includes passive SFs, such as gorgonians or crinoids that use the ambient flow to encounter particles, and sponges, bivalves or baleen whales, which actively create a feeding current. Separation media can be flat or funnel-shaped, built externally such as the filter houses in larvaceans, or internally, like the pleated gills in bivalves. Most SFs feed in the intermediate flow region of Reynolds number 1-50 and have cleaning mechanisms that allow for continuous feeding. Comparison of structure-function patterns in SFs to current filtration technologies highlights potential solutions to common technical design challenges, such as mucus nets which increase particle adhesion in ascidians, vanes which reduce pressure losses in whale sharks and changing mesh sizes in the flamingo beak which allow quick adaptation to particle sizes.
Topics: Animals; Biomimetics; Feeding Behavior; Plankton; Sharks; Suspensions
PubMed: 35078340
DOI: 10.1098/rsif.2021.0741 -
International Journal of Antimicrobial... Dec 2023To investigate the potential impact of clinical characteristics and the Chinese race on posaconazole pharmacokinetics in patients using an integrated population...
Meta-pharmacokinetic analysis of posaconazole following dosing of oral suspension, delayed-release tablet, and intravenous infusion in patients vs. healthy volunteers: Impact of clinical characteristics and race.
OBJECTIVES
To investigate the potential impact of clinical characteristics and the Chinese race on posaconazole pharmacokinetics in patients using an integrated population pharmacokinetic model for posaconazole oral suspension (SUS), delayed-release tablet (DR-tablet), and intravenous (IV) infusion that was developed in healthy volunteers (HV).
METHODS
1046 concentrations from 105 prospectively studied Caucasian patients receiving either of the three posaconazole formulations were pooled with 3898 concentrations from 182 HV. Clinical characteristics were tested for significance. The impact of Chinese race was assessed using 292 opportunistic samples from 80 Chinese patients receiving SUS.
RESULTS
Bioavailability of SUS (F) in patients decreased from 38.2% to 24.6% when the dose was increased from 100 mg to 600 mg. Bioavailability of DR-tablet (F) was 59% regardless of dose. Mucositis, diarrhoea, administration through a nasogastric tube, and concomitant use of proton pump inhibitors or metoclopramide reduced F by 61%, 36%, 44%, 48%, and 29%, respectively, putting patients with these characteristics at increased risk of inadequate exposure. Clearance decreased from 7.0 to 5.1 L/h once albumin levels were <30 g/L. Patients showed an 84.4% larger peripheral volume of distribution (V) and 67.5% lower intercompartmental clearance (Q) compared with HV. No racial difference could be identified.
CONCLUSIONS
Pharmacokinetics of posaconazole in patients differ considerably to those in HV, with altered F that is also impacted by clinical covariates, an F similar to fasted conditions in HV, and altered parameters for clearance, V, and Q. There was no evidence to indicate that Chinese patients require a different dose to Caucasian patients.
Topics: Humans; Infusions, Intravenous; Antifungal Agents; Tablets; Triazoles; Biological Availability; Suspensions; Administration, Oral
PubMed: 37806462
DOI: 10.1016/j.ijantimicag.2023.106995 -
European Journal of Pharmaceutics and... Mar 2022Rapid precorneal loss of topically applied eye drops limits ocular drug absorption. Controlling release and precorneal residence properties of topical formulations may...
Rapid precorneal loss of topically applied eye drops limits ocular drug absorption. Controlling release and precorneal residence properties of topical formulations may improve ocular drug bioavailability and duration of action. In this study, we evaluated in vivo ocular pharmacokinetics of dexamethasone in rabbits after application of a drug solution (0.01%), suspension (Maxidex® 0.1%), and hydrogels of 2-hydroxyethyl methacrylate (HEMA) and acrylic acid (AAc) copolymers. The rabbits received a single eyedrop (solution or suspension) or dexamethasone-loaded hydrogel topically. Dexamethasone in tear fluid was sampled with glass capillaries and quantitated by LC-MS/MS. Higher dexamethasone exposure (AUC) in the tear fluid was observed with the suspension (≈3.6-fold) and hydrogel (12.8-fold) as compared to the solution. During initial 15 min post-application, the highest AUC of dissolved dexamethasone was seen after hydrogel application (368 min*µg/mL) followed by suspension (109.9 min*µg/mL) and solution (28.7 min*µg/mL. Based on kinetic simulations, dexamethasone release from hydrogels in vivo and in vitro is comparable. Our data indicate that prolonged exposure of absorbable dexamethasone in tear fluid is reached with hydrogels and suspensions. Pharmacokinetic understanding of formulation behavior in the lacrimal fluid helps in the design of dexamethasone delivery systems with improved ocular absorption and prolonged duration of action.
Topics: Animals; Chromatography, Liquid; Dexamethasone; Drug Liberation; Hydrogels; Kinetics; Rabbits; Suspensions; Tandem Mass Spectrometry
PubMed: 35121080
DOI: 10.1016/j.ejpb.2022.01.005 -
Epidemiology and Infection Apr 2023This experimental study aimed to determine the activity of a near-UVA (405 nm) LED ceiling system against the SARS-CoV-2 virus. The ceiling system comprised 17 near-UVA...
This experimental study aimed to determine the activity of a near-UVA (405 nm) LED ceiling system against the SARS-CoV-2 virus. The ceiling system comprised 17 near-UVA LED lights with a radiant power of 1.1 W/each centred at 405 nm wavelength. A 96-multiwell plate, fixed to a wooden base, was inoculated with suspensions of VERO E6 cell cultures infected with SARS-CoV-2 virus and irradiated at a distance of 40 cm with a dose of 20.2 J/cm for 120 min. The collected suspensions were transferred to VERO cell culture plates and incubated for 3 days. The maximum measurable log reduction obtained, starting from a concentration of 10 TCID50/mL, was 3.0 log and indicated inhibition of SARS-CoV-2 replication by the near-UVA LED ceiling system. Near-UVA light at a 405-nm wavelength is emerging as a potential alternative treatment for localised infections and environmental decontamination because it is far less harmful to living organisms' cells than UV-C irradiation.
Topics: Animals; Chlorocebus aethiops; COVID-19; SARS-CoV-2; Suspensions; Ultraviolet Rays; Vero Cells
PubMed: 37100744
DOI: 10.1017/S0950268823000560