ethyl-cellulose has been researched along with Disease-Models--Animal* in 6 studies
6 other study(ies) available for ethyl-cellulose and Disease-Models--Animal
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Neuroprotective effect of melatonin loaded in ethylcellulose nanoparticles applied topically in a retinal degeneration model in rabbits.
We are reporting for the first time the synthesis and application of an innovative nanometric system for the controlled topic release of melatonin in the retina. The ethylcellulose nanocapsules were characterized by diverse physicochemical techniques (scanning electron microscopy, zeta potential, hydrodynamic diameters) and an in vitro release study was done. A complete ex vivo and in vivo trans-corneal permeation and an irritation study were carried out with the new formulations in albino rabbits, to which a retinal degenerative model was induced. The results obtained demonstrate that the in vitro release of melatonin (1 mg/mL and 2 mg/mL) transported by nanocapsules is slower when compared to a solution of melatonin. Greater penetration of melatonin through the cornea was demonstrated by ex vivo and in vivo tests. This can be attributable to an enhanced neuroprotective effect of melatonin on retinal ganglion cells when it is included in ethylcellulose nanocapsules compared to a solution of melatonin. These outstanding findings add promising new perspectives to current knowledge about administrations using nano-technological tools in the treatment of neurodegenerative diseases at the ocular level. Topics: Animals; Antioxidants; Cellulose; Disease Models, Animal; Drug Compounding; Melatonin; Microscopy, Electron, Scanning; Nanoparticles; Rabbits; Retinal Degeneration; Retinal Ganglion Cells | 2020 |
Development of enhanced ethanol ablation as an alternative to surgery in treatment of superficial solid tumors.
While surgery is at the foundation of cancer treatment, its access is limited in low-income countries. Here, we describe development of a low-cost alternative therapy based on intratumoral ethanol injection suitable for resource-limited settings. Although ethanol-based tumor ablation is successful in treating hepatocellular carcinomas, the necessity for multiple treatments, injection of large fluid volumes, and decreased efficacy in treatment of non-capsulated tumors limit its applicability. To address these limitations, we investigated an enhanced ethanol ablation strategy to retain ethanol within the tumor through the addition of ethyl cellulose. This increases the viscosity of injected ethanol and forms an ethanol-based gel-phase upon exposure to the aqueous tumor environment. This technique was first optimized to maximize distribution volume, using tissue-simulating phantoms. Then, chemically-induced epithelial tumors in the hamster cheek pouch were treated. As controls, pure ethanol injections of either four times or one-fourth the tumor volume induced complete regression of 33% and 0% of tumors, respectively. In contrast, ethyl cellulose-ethanol injections of one-fourth the tumor volume induced complete regression in 100% of tumors. These results contribute to proof-of-concept for enhanced ethanol ablation as a novel and effective alternative to surgery for tumor treatment, with relevance to resource-limited settings. Topics: Animals; Catheter Ablation; Cell Line, Tumor; Cell Survival; Cellulose; Cricetinae; Disease Models, Animal; Ethanol; Female; Humans; Injections, Intralesional; Neoplasms; Phantoms, Imaging; Treatment Outcome; Tumor Burden; Xenograft Model Antitumor Assays | 2017 |
Preparation and evaluation of colon adhesive pellets of 5-aminosalicylic acid.
Oral modified-release delivery systems, such as bio-adhesive one, enable drug delivery to affected regions and minimize the side effects by reducing the systemic absorption. Our aim was to develop colon adhesive pellets of 5-aminosalicylic acid (5-ASA) for the treatment of ulcerative colitis. The core of the pellet was formulated from bioadhesive agents, Carbomer 940 and hydroxypropyl cellulose (HPC), by extrusion/spheronization method and coated with Surelease(®) as inner layer for waterproof and with Eudragit(®) S100 as outer layer for pH control. The rat model of ulcerative colitis was used to evaluate the efficiency of our loaded pellets as a drug carrier. Microcrystalline cellulose 101 (PH 301) was found to be the best agent for pellet core. The ratio of CP940 to HPC should be kept as (1:1) to achieve high bioadhesion. When the amount of Surelease(®) was from 16% to 20% and of Eudragit(®) S100 was 28%, the dissolution profiles of coated pellets revealed no drug release in the artificial gastric fluid (pH 1.0) within 2h and less than 10% was released in phosphate buffer (pH 6.0) within 2h whereas complete dissolution was observed in colonic fluid of pH 7.4 for 20 h. The animal experiment showed that 5-ASA loaded colon adhesive pellets had optimal therapeutic effect. We showed a novel approach to prepare effective bioadhesive pellets as colon targeted drug delivery system. Topics: Acrylic Resins; Adhesiveness; Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Biomarkers; Cellulose; Chemistry, Pharmaceutical; Colitis, Ulcerative; Colon; Disease Models, Animal; Drug Carriers; Excipients; Kinetics; Male; Mesalamine; Polymethacrylic Acids; Rats, Sprague-Dawley; Solubility; Tablets, Enteric-Coated; Technology, Pharmaceutical; Trinitrobenzenesulfonic Acid | 2014 |
Biodegradable ocular inserts for sustained delivery of brimonidine tartarate: preparation and in vitro/in vivo evaluation.
The bioavailability of therapeutic agents from eye drops is usually limited due to corneal barrier functions and effective eye protective mechanisms. Therefore, the current study aims to enhance ocular bioavailability of brimonidine, a potent antiglaucoma drug, through the preparation of ocular inserts. Solvent casting technique was employed to prepare the inserts using polyvinylpyrrolidone K-90 (PVP K-90) as film-forming polymer blended with different viscosity grades of bioadhesive polymers namely hydroxypropyl methycellulose, carbopol, sodium alginate, and chitosan. The prepared ocular inserts were evaluated for various physicochemical parameters, swelling behavior, and in vitro release patterns. Sodium alginate-based ocular inserts revealed the most sustainment in drug release (99% at 6 h), so it was selected for further modifications via coating it, on one side or dual sides, using hydrophobic film composed of either ethylcellulose or Eudragit RSPO. The obtained in vitro release results for the modified ocular inserts revealed that ethylcellulose is superior to Eudragit RSPO in terms of brimonidine release sustainment effect. Ocular inserts composed of 7% PVP K-90, 1.5% low molecular weight sodium alginate with or without ethylcellulose coat were able to sustain the in vitro release of brimonidine. Their therapeutic efficacy regarding intraocular pressure (IOP) lowering effect when inserted in albino rabbits eyes showed superior sustainment effect compared with that of brimonidine solution. Furthermore, due to both the mucoadhesive property and the drug sustainment effect, the one-side-coated ocular insert showed more IOP lowering effect compared with that of its non-coated or dual-side-coated counterpart. Topics: Absorbable Implants; Acrylic Resins; Administration, Ophthalmic; Adrenergic alpha-2 Receptor Agonists; Alginates; Animals; Brimonidine Tartrate; Calorimetry, Differential Scanning; Cellulose; Chemistry, Pharmaceutical; Chitosan; Delayed-Action Preparations; Disease Models, Animal; Drug Carriers; Drug Compounding; Glaucoma; Glucuronic Acid; Hexuronic Acids; Hydrophobic and Hydrophilic Interactions; Hypromellose Derivatives; Intraocular Pressure; Kinetics; Methylcellulose; Ophthalmic Solutions; Polymers; Polymethacrylic Acids; Polyvinyls; Povidone; Quinoxalines; Rabbits; Solubility; Spectroscopy, Fourier Transform Infrared; Technology, Pharmaceutical; X-Ray Diffraction | 2011 |
Development of controlled release captopril granules coated with ethylcellulose and methylcellulose by fluid bed dryer.
Captopril granules of controlled release with different polymers as ethylcellulose, ethyl/methylcellulose, and immediate release with polyvinylpyrrolidone (PVP) were developed by fluid bed dryer technique. The formulations were analyzed by scanning electron microscopy, X-ray powder diffraction, and dissolution profiles. To compare the formulations an in vivo setting rat blood pressure assay was performed, using angiotensin I as a vasoconstrictor agent. The scanning electron microscopy of granules showed differences in morphology, and X-ray powder diffraction technique presented some modification in crystalline structure of captopril in granules coated with PVP and ethyl/methylcellulose. The dissolution profile of granules coated with ethylcellulose showed a median time release of 4 hr whereas for granules coated with ethyl/methylcellulose, this time was 3.5 hr. The blockage of angiotensin I-induced hypertensive effect lasted 8 hr in granules coated with PVP and of more than 12 hr in the granules coated with ethylcellulose and ethyl/methylcellulose. Topics: Administration, Oral; Angiotensin I; Angiotensin-Converting Enzyme Inhibitors; Animals; Antihypertensive Agents; Blood Pressure; Captopril; Cellulose; Chemistry, Pharmaceutical; Crystallography, X-Ray; Delayed-Action Preparations; Disease Models, Animal; Drug Compounding; Female; Hypertension; Kinetics; Methylcellulose; Microscopy, Electron, Scanning; Models, Chemical; Povidone; Powder Diffraction; Powders; Rats; Rats, Wistar; Solubility; Technology, Pharmaceutical | 2008 |
Percutaneous internal maxillary arterial embolization with ethylcellulose microspheres. Results in an animal model.
To investigate the use of ethylcellulose microspheres as long-term and peripheral emboli for percutaneous maxillofacial arterial embolization.. Eight mongrel dogs were selected randomly for internal maxillary artery embolization with ethylcellulose microspheres. After embolization, angiographic, microangiographic, and histologic examinations were performed.. Ethylcellulose microspheres were trapped in the peripheral arterioles from 24 hours to 6 months after embolization. Degenerative changes of maxilla, mandible, and dental pulp occurred after the embolization of the internal maxillary artery with the microspheres. No evidence of whole or focal necrosis of the bones and surrounding soft tissues was found between 24 hours and 6 months after embolization.. Ethylcellulose microspheres can be used as an alternative long-term and peripheral embolic agent, with potential for percutaneous maxillofacial arterial embolization. Topics: Angiography, Digital Subtraction; Animals; Arterioles; Calcinosis; Catheterization, Peripheral; Cellulose; Dental Pulp; Dental Pulp Calcification; Disease Models, Animal; Dogs; Embolization, Therapeutic; Follow-Up Studies; Haversian System; Mandible; Maxilla; Maxillary Artery; Microradiography; Microspheres; Periodontal Diseases; Thrombosis | 1995 |