Search results for "Drug carrier"
showing 10 items of 329 documents
Gold nanostar–polymer hybrids for siRNA delivery: Polymer design towards colloidal stability and in vitro studies on breast cancer cells
2017
To overcome the low bioavailability of siRNA (small interfering RNA) and to improve their transfection efficiency, the use of non-viral delivery carriers is today a feasible approach to transform the discovery of these incredibly potent and versatile drugs into clinical practice. Polymer-modified gold nanoconstructs (AuNCs) are currently viewed as efficient and safe intracellular delivery carriers for siRNA, as they have the possibility to conjugate the ability to stably entrap and deliver siRNAs inside cells with the advantages of gold nanoparticles, which can act as theranostic agents and radiotherapy enhancers through laser-induced hyperthermia. In this study, AuNCs were prepared by coat…
1H NMR methodologies applied in the thermodynamic and structural characterization of organic supramolecular complexes
2021
Orientador: Anita Jocelyne Marsaioli Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Nesta tese consiste no estudo de interações supramoleculares utilizando diferentes metodologias de Ressonância Magnética Nuclear de hidrogênio (RMN de 1H), tais como ROESY 1D, RMN-DOSY e RMN-STD. Os sistemas supramoleculares foram abordados em dois casos de estudo diferentes. O Capítulo I tem como objeto de estudo interações do fármaco Dapsona com diferentes carreadores de fármacos (ß-CD, SBE-ß-CD e lipossoma de EPC), com a finalidade de encontrar formulações nas quais a Dapsona seja mais solúvel. Os complexos binários e ternário formados foram determinadas por medidas de …
Trehalose-hydroxyethylcellulose microspheres containing vancomycin for topical drug delivery.
2001
Abstract A new formulation, in which vancomycin is entrapped into trehalose and hydroxyethylcellulose (Natrosol ® ) spherical matrices, is described. Microspheres were produced by the solvent evaporation method. The entrapped drug was fully recovered following microspheres dissolution. Differential scanning calorimetry analyses proved that Natrosol maintains trehalose in its amorphous form. The stabilizing effects of trehalose on vancomycin were evaluated even after long storage and heating of microspheres. Calorimetric data indicated no decomposition of the entrapped drug. In vitro drug release, already performed by using a general two-compartment linear time-invariant open model, suggests…
Pefloxacine mesilate- and ofloxacin-loaded polyethylcyanoacrylate nanoparticles: characterization of the colloidal drug carrier formulation.
1995
The entrapment of fluoroquinolones, perfloxacine mesilate (PFX) and ofloxacin (OFX), in polyalkylcyanoacrylate (PECA) nanoparticles could offer some advantages for their biological application; for examples, increasing their bioavailability, controlling the drug time-release in blood, and reducing the formation of bacterial resistance. To load these two drugs in PECA polymeric bulk, the incorporation or adsorption method was performed. These two methods were capable of influencing nanoparticle size, molecular weight, release profile, and drug–polymer association. The incorporation method, particularly for the OFX system, achieved PECA nanoparticle suspensions with a mean size value three ti…
Inhibition of skin inflammation by baicalin ultradeformable vesicles.
2016
The topical efficacy of baicalin, a natural flavonoid isolated from Scutellaria baicalensis Georgi, which has several beneficial properties, such as antioxidative, antiviral, anti-inflammatory and antiproliferative, is hindered by its poor aqueous solubility and low skin permeability. Therefore, its incorporation into appropriate phospholipid vesicles could be a useful tool to improve its local activity. To this purpose, baicalin at increasing concentrations up to saturation, was incorporated in ultradeformable vesicles, which were small in size (∼67nm), monodispersed (PI<0.19) and biocompatible, regardless of the concentration of baicalin, as confirmed by in vitro studies using fibroblasts…
The Influence of Chitosan on the Oral Bioavailability of Acyclovir-a Comparative Bioavailability Study in Humans
2015
Purpose The effects of chitosan hydrochloride on the oral absorption of acyclovir in humans were studied to confirm the absorption enhancing effects reported for in vitro and rat studies, respectively. Methods A controlled, open-label, randomized, 3-phase study was conducted in 12 healthy human volunteers. Zovirax 200 mg dispersible tablets co-administered with doses of 400 and 1000 mg chitosan HCl were compared with Zovirax only. Results The expected increased absorption of acyclovir was not observed. On the contrary, mean area under the plasma concentration-time curve (AUC0-12 h) and maximal plasma concentration (Cmax) decreased following concomitant chitosan intake (1402 versus 1017 and …
Role of a 48-week pegylated interferon therapy in hepatitis B e antigen positive HIV-co-infected patients on cART including tenofovir: EMVIPEG study.
2014
In hepatitis B e antigen (HBeAg) positive-HIV co-infected patients treated with combined antiretroviral therapy (cART), including tenofovir disoproxil fumarate (TDF), the rate of HBe seroconversion remains low. Whether adding pegylated interferon alfa (PegIFN) could increase the likelihood of HBeAg loss and HBe seroconversion has not been assessed.A 48-week PegIFN therapy was added to HBeAg positive-HIV co-infected patients on TDF and emtricitabine, or lamivudine for at least 6 months. The primary endpoint was HBV sustained response: HBe seroconversion with undetectable HBV DNA levels 24 weeks after completing PegIFN therapy (W72).Fifty-one patients (49 men, median age 46 years, range: 32-6…
Defer or treat? Reasons for treatment decisions in patients with chronic hepatitis C genotype 1 in the early era of directly acting antiviral agents
2013
Abstract Background In chronic genotype 1 hepatitis C, telaprevir or boceprevir plus peginterferon and ribavirin have become the new standard of care. Aim of this study was to identify factors contributing to the decision whether to defer or treat with the current triple regimens. Methods Prospective assessment of eight parameters on 0-4-point scales by the attending physician at a German tertiary referral centre between 1st September 2011 and 31st December 2012. Results 307 patients were evaluated at least once by one of the 11 hepatologists involved; 267 patients were considered, but only 163 were recommended to receive triple therapy. Multivariate regression analysis revealed that a high…
Clinical and economic impact of drug eluting beads in transarterial chemoembolization for hepatocellular carcinoma
2015
Summary What is known and objective Drug eluting beads (DEBs) theoretically improve the efficacy and safety of transarterial chemoembolization (TACE) in hepatocellular carcinoma (HCC). Nonetheless, their economic profile has not been assessed. Our retrospective before/after study aimed to compare efficacy, safety and economic profile of two strategies of TACE without (Period 1) or with the possibility of using DEBs (Period 2). Methods All HCC patients treated by TACE in our hospital between March 2006 and May 2013 were included. Economic analyses were performed from the French Public Health Insurance point of view according to the French Diagnosis-Related Group prospective payment system an…
Targeted Hybrid Nanocarriers as a System Enhancing the Skin Structure
2021
The skin is constantly exposed to external and internal factors that disturb its function. In this work, two nanosystems-levan nanoparticles and a surfactin-stabilized nanoemulsion were preserved (tested for microbial growth) and characterized (size, polydispersity, Zeta potential, and stability). The nanosystems were introduced in the model formulations-cream, tonic, and gel, and confirmed by TEM. The analysis showed that nanoemulsion has a spherical morphology and size 220–300 nm, while levan nanoparticles had irregular shapes independently of the use of matrix and with particle size (130–260 nm). Additionally, we examined the antiradical effect of levan nanoparticles and nanoemulsion in …