Crosslinked Poly(Methyl Vinyl Ether-Co-Maleic Anhydride) as Topical Vehicles for Hydrophilic and Lipophilic Drugs

Poly(methyl vinyl ether-co-maleic anhydride) crosslinked with ethylene glycol (GZ-ET), 1,4-butanediol (GZ-BUT), 1,6-exandiol (GZ-EX), 1,8-octanediol (GZ-OCT), 1,10-decanediol (GZ-DEC) or 1,12-dodecanediol (GZ-DOD) was prepared and employed as a supporting material for aqueous topical gels containing pyridoxine hydrochloride (PYCL) chosen as a hydrophilic model molecule or for O/A emulsion containing beta-carotene chosen as a hydrophobic model molecule. We analyzed the effect of the nature of the crosslinker on the permeation of hydrophilic and lipophilic vitamins through porcine skin by in vitro permeation studies. The vehicles formed by crosslinked poly(methyl vinyl ether-co-maleic anhydride) showed enhanced vitamins permeation with respect to the same vehicles formed by noncrosslinked poly(methyl vinyl ether-co-maleic anhydride) (GZ). The decrease in the crosslinker acyl chain length provides vehicles accelerating the drug permeability through the skin

Poly(Vinylalcohol-Co-Vinyloleate) for the Preparation of Micelles Enhancing Retinyl Palmitate Transcutaneous Permeation

The amphiphilic properties of poly(vinylalcohol) substituted with oleic acid was evaluated to assess the possibility to prepare polymeric micelles in an aqueous phase containing a hydrophobic core able to host lipophilic drugs such as retinyl palmitate and thereby enhance its transcutaneous absorption in the stratum corneum. The effect of the increased drug absorption suggests the possibility of interaction between the substituted polymer and the components present in the intercorneocyte spaces. Correlations between the drug concentration in the preparative mixture, micelle size, and drug permeation were evaluated to establish the best functional properties of the micellar systems enhancing retinyl palmitate absorption. Transcutaneous absorption increased with decreasing micelle size, and micelle size decreased on decreasing the drug concentration in the preparative mixture

Drug delivery to the brain: In situ gelling formulation enhances carbamazepine diffusion through nasal mucosa models with mucin

The objective of this work was to optimize a thermosensitive in situ gelling formulation to improve intranasal and nose-to-brain delivery of the antiepileptic drug carbamazepine (CBZ). A preliminary procedure of vehicles obtained just mixing different fractions of poloxamer 407 (P407) and poloxamer 188 (P188) revealed preparations with phase transition temperatures, times to gelation and pH values suitable for nasal delivery. Subsequently, the mucoadhesive properties of the most promising formulations were tuned by adding hydroxypropylmethylcellulose types of different viscosity grades, and the effect of the adhesive polymers was evaluated by testing in vitro time and strength of mucoadhesion on specimens of sheep nasal mucosa. The formulation that showed the greatest mucoadhesive potential in vitro, with a time and force of mucoadhesion equal to 1746,75 s and 3.66 × 10-4 N, respectively, was that composed of 22% P407, 5% P188 and 0.8% HPMC low-viscous and it was further investigated for its ability to increase drug solubility and to control the release of the drug. Lastly, the capability of the candidate vehicle to ensure drug permeation across the biomimetic membrane Permeapad®, an artificial phospholipid-based barrier with a stratified architecture, and the same barrier enriched with a mucin layer was verified. The final formulation was characterized by a pH value of 6.0, underwent gelation at 32.33°C in 37.85 s, thus showing all the features required by in situ gelling thermosensitive preparations designed for nasal delivery and, more notably, it conserved the ability to favor drug permeation in the presence of mucin. These findings suggest that the optimized gelling system could be a promising and easy to realize strategy to improve CBZ delivery to the brain exploiting both a direct and indirect pathway

Design and Characterization of an Ethosomal Gel Encapsulating Rosehip Extract

© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Rising environmental awareness drives green consumers to purchase sustainable cosmetics based on natural bioactive compounds. The aim of this study was to deliver Rosa canina L. extract as a botanical ingredient in an anti-aging gel using an eco-friendly approach. Rosehip extract was first characterized in terms of its antioxidant activity through a DPPH assay and ROS reduction test and then encapsulated in ethosomal vesicles with different percentages of ethanol. All formulations were characterized in terms of size, polydispersity, zeta potential, and entrapment efficiency. Release and skin penetration/permeation data were obtained through in vitro studies, and cell viability was assessed using an MTT assay on WS1 fibroblasts. Finally, ethosomes were incorporated in hyaluronic gels (1% or 2% w/v) to facilitate skin application, and rheological properties were studied. Rosehip extract (1 mg/mL) revealed a high antioxidant activity and was successfully encapsulated in ethosomes containing 30% ethanol, having small sizes (225.4 ± 7.0 nm), low polydispersity (0.26 ± 0.02), and good entrapment efficiency (93.41 ± 5.30%). This formulation incorporated in a hyaluronic gel 1% w/v showed an optimal pH for skin application (5.6 ± 0.2), good spreadability, and stability over 60 days at 4 °C. Considering sustainable ingredients and eco-friendly manufacturing technology, the ethosomal gel of rosehip extract could be an innovative and green anti-aging skincare product.The authors are thankful to Sofia Melo Rocha for her contribution to the work. The authors thank the Fundação para a Ciência e Tecnologia, Portugal (UIDB/04138/2020 and UIDP/04138/2020 for iMed.ULisboa, CEECINST/00145/2018 for J. Marto, and CEEC-IND/03143/2017 for L. M. Gonçalves).info:eu-repo/semantics/publishedVersio

Paediatric recurrent pericarditis: Appropriateness of the standard of care and response to IL1-blockade

Objective: To analyse, in a cohort of paediatric patients with recurrent pericarditis (RP) undergoing anti-IL-1 treatment: the agent and dosing used as first line treatment, the long-term efficacy of IL1-blockers, the percentage of patients achieving a drug-free remission, the presence of variables associated with drug-free remission. Study design: Data were collected from patients' charts. Annualized relapse rate (ARR) was used for evaluation of treatment efficacy, bivariate logistic regression analysis for variables associated with drug-free remisison. Results: 58 patients, treated between 2008 and 2018, were included in the study (mean follow-up 2.6 years). 14/56 patients non-responsive to first line drugs were under-dosed. 57 patients were treated with anakinra: the ARR before and during daily treatment was 3.05 and 0.28, respectively (p<0.0001); an increase to 0.83 was observed after the reduction/withdrawal of treatment (p<.0001). The switch from anakinra to canakinumab (5 patients) was associated to an increase of the ARR (0.49 vs 1.46), but without statistical significance (p=0.215). At last follow-up only 9/58 patients had withdrawn all treatments. With the limits of a retrospective study and the heterogeneity between the patients enrolled in the study, a shorter duration of treatment with anakinra was the only variable associated with drug-free remission. Conclusion: This study shows that most of the pediatric patients with RP needing IL-1 blockade received an inadequate treatment with first line agents. The effectiveness of anakinra is supported by this study, but few patients achieved drug free-remission. The different rate of response to anakinra and canakinumab may suggest a possible role of IL1α in the pathogenesis of RP

Gastrointestinal presentation of kawasaki disease: A red flag for severe disease?

Background Kawasaki disease (KD) is a febrile systemic vasculitis of unknown etiology and the main cause of acquired heart disease among children in the developed world. To date, abdominal involvement at presentation is not recognized as a risk factor for a more severe form of the disease. Objective To evaluate whether presenting abdominal manifestations identify a group at major risk for Intravenous immunoglobulin (IVIG)-resistance and coronary lesions. Methods Retrospective study of KD patients diagnosed between 2000 and 2015 in 13 pediatric units in Italy. Patients were divided into 2 groups according to the presence or absence of abdominal manifestations at onset. We compared their demographic and clinical data, IVIG-responsiveness, coronary ectasia/aneurysms, laboratory findings from the acute and subacute phases. Results 302 patients (181 boys) were enrolled: 106 patients with, and 196 patients without presenting abdominal features. Seasonality was different between the groups (p = 0.034). Patients with abdominal manifestations were younger (p = 0.006) and more frequently underwent delayed treatment (p = 0.014). In the acute phase, patients with abdominal presentation had higher platelet counts (PLT) (p = 0.042) and lower albuminemia (p = 0.009), while, in the subacute phase, they had higher white blood cell counts (WBC) and PLT (p = 0.002 and p < 0.005, respectively) and lower red blood cell counts (RBC) and hemoglobin (Hb) (p = 0.031 and p 0.009). Moreover, the above mentioned group was more likely to be IVIG-resistant (p < 0.005) and have coronary aneurysms (p = 0.007). In the multivariate analysis, presenting abdominal manifestations, age younger than 6 months, IVIG- resistance, delayed treatment and albumin concentration in the acute phase were independent risk factors for coronary aneurysms (respectively p<0.005, <0.005, = 0.005 and 0.009). Conclusions This is the first multicenter report demonstrating that presenting gastrointestinal features in KD identify patients at higher risk for IVIG-resistance and for the development of coronary aneurysms in a predominantly Caucasian population

Gastroresistant microcapsules: new approaches for site-specific delivery of ketoprofen

Ketoprofen is a potent nonsteroidal anti-inflammatory drug (NSAID) that has been widely used in the treatment of rheumatoid arthritis and other related conditions. However, it carry the risk of undesirable systemic side effects and gastrointestinal irritation at the usual dose of oral administration. The aim of this study was to prepare and evaluate gastroresistant microcapsules containing ketoprofen. Microcapsules were obtained by a spray-drying process starting from a O/A emulsion in presence of different pH-dependent materials (Eudragit® L100, Eudragit® S100 and stearic acid) dissolved in the external phase. The influence of formulation factors (oily phase employed for drug solubilisation, type of coating) on the morphology, particle size distribution, drug loading capacity, in-vitro release and ex-vivo permeation characteristics were investigated. Drug loading capacity was very high for all the microcapsules prepared. Formulation factors did not significatively influence the mean particle size, but modified microcapsule in-vitro and ex-vivo behaviour

Formulation of cellulose film containing permeation enhancers for prolonged delivery of propranolol hydrocloride

The aim of this study was to evaluate the capacity of cellulose films enriched with oleic acid and polysorbate 80 to enhance the transdermal permeation of propranolol hydrochloride. Polymeric films were prepared by casting and drying aqueous solutions of hydroxypropylmethylcellulose or carboxymethylcellulose and characterized in chemical\u2013physical properties, such as drug content, thickness, morphology and water uptake capacity. In vitro transport experiments were performed in order to evaluate the permeation enhancing ability of oleic acid and polysorbate 80. All carboxymethylcellulose films showed lower cumulative amounts of drug permeated than hydroxypropylmethylcellulose. Moreover, films containing both oleic acid and polysorbate 80 provided a greater permeation in comparison to film without permeation enhancers or only with one of these. The results obtained confirm that propranolol hydrochloride permeation can be easily modulated by varying the cellulose and enhancer type used for film preparation

Microparticles based on chitosan/pectin polyelectrolyte complexes for nasal delivery of tacrine hydrochloride

The aim of this study was the investigation of powder-based formulations for nasal administration of tacrine hydrochloride. The anti-Alzheimer drug was encapsulated in mucoadhesive microparticles based on chitosan/pectin polyelectrolyte complexes. Microparticles were prepared by means of two different technological approaches (direct spray-drying and spray-drying followed by lyophilization) and analysed in terms of size, morphology and physico-chemical characteristics. Moreover, water uptake and mucoadhesion ability were evaluated as well as drug release and permeation behaviour. The results suggest that lyophilization favours the formation of small particle aggregates with a size of 10 \u3bcm, instead of single particles (size smaller than 5 \u3bcm) such as direct spray-drying. Particles obtained with the two loading methods present different functional properties according to the different physical state of the loaded drug and its possible interaction with chitosan/pectin complex. Moreover, the presence of different amount of chitosan and pectin in the complex influences their ability to hydrate, interact with mucin and favour drug permeation