Drug-Loaded Polymeric Particulated Systems for Ophthalmic Drugs Release.

Drug delivery to the anterior or posterior segments of the eye is a major challenge due to the protection barriers and removal mechanisms associated with the unique anatomical and physiological nature of the ocular system. The paper presents the preparation and characterization of drug-loaded polymeric particulated systems based on pre-emulsion coated with biodegradable polymers. Low molecular weight biopolymers (chitosan, sodium hyaluronate and heparin sodium) were selected due to their ability to attach polymer chains to the surface of the growing system. The particulated systems with dimensions of 190-270 nm and a zeta potential varying from -37 mV to +24 mV depending on the biopolymer charges have been obtained. Current studies show that particles release drugs (dexamethasone/pilocarpine/bevacizumab) in a safe and effective manner, maintaining therapeutic concentration for a longer period of time. An extensive modeling study was performed in order to evaluate the drug release profile from the prepared systems. In a multifractal paradigm of motion, nonlinear behaviors of a drug delivery system are analyzed in the fractal theory of motion, in order to correlate the drug structure with polymer. Then, the functionality of a SL(2R) type "hidden symmetry" implies, through a Riccati type gauge, different "synchronization modes" (period doubling, damped oscillations, quasi-periodicity and intermittency) during the drug release process. Among these, a special mode of Kink type, better reflects the empirical data. The fractal study indicated more complex interactions between the angiogenesis inhibitor Bevacizumab and polymeric structure.

Leber's hereditary optic neuropathy - Case report.

Leber's hereditary optic neuropathy is the most common mitochondrial condition and is characterized by bilateral, painless, subacute visual loss that develops during young adult life. LHON is a rare condition and this lack of knowledge can make doctors suspect and treat for other causes of vision loss. Typically, a series of tests are performed to confirm LHON diagnosis or exclude any other conditions. We presented the case of two brothers, HB, of 40 years old and HF, of 38 years old, who presented with a decrease in visual acuity in both eyes. The patients had been diagnosed with optic atrophy of unknown cause a long time ago, but no further investigations were made. They were treated with corticosteroids, antioxidants and vasodilators, but with no significant benefit. A blood test of the mitochondrial DNA, a magnetic resonance imaging and an optic coherence tomography of the optic nerve and macula were part of the following assessment of our patients. The mitochondrial DNA analyses revealed the 3460 G>A mutation on the mtND1 gene in both patients. Based on the medical history, the fundus aspect, the optic coherence tomography and the paraclinical investigations of the diagnosis of Leber's hereditary optic neuropathy were established in both patients. We started the treatment with idebenone and we evaluated the patients after three months. ABBREVIATIONS: LHON = Leber's hereditary optic neuropathy, mtDNA = mitochondrial DNA, VA = visual acuity, CF = count fingers, OCT = optical coherence tomography, RNFL = retinal nerve fiber layer, GCL = ganglion cells layer, MS = multiple sclerosis, MRI = magnetic resonance imaging, MTI = magnetization transfer imaging, MTR = magnetization transfer ratio.

Terson's Syndrome - case report.

Terson's Syndrome is represented by a vitreous, retrohyaloid, retinal, or subretinal hemorrhage occurring consequent to an acute intracranial hemorrhage or elevated intracranial pressure. The outcome may include a complete clearing of the blood and the restoration of VA or persistent hemorrhage. This report presents the case of a 43-year-old woman who underwent bilateral surgery for a persistent vitreous hemorrhage and a hematoma underneath the internal limiting membrane in the left eye. The event followed shortly after a subarachnoid hemorrhage due to the rupture of a posterior communicating artery aneurism. Vitrectomy was performed in both eyes, together with the peeling of the internal limiting membrane in the left eye, followed by a bilateral good outcome.