LEANDRO CABRAL ZACHARIAS
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/33 - Laboratório de Oftalmologia, Hospital das Clínicas, Faculdade de Medicina
LIM/33 - Laboratório de Oftalmologia, Hospital das Clínicas, Faculdade de Medicina
6 resultados
Resultados de Busca
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- OPTICAL COHERENCE TOMOGRAPHY ANALYSIS OF OUTER RETINAL TUBULATIONS Sequential Evolution and Pathophysiological Insights(2018) PRETI, Rony C.; GOVETTO, Andrea; AQUETA FILHO, Richard Geraldo; ZACHARIAS, Leandro Cabral; PIMENTEL, Sergio Gianotti; TAKAHASHI, Walter Y.; MONTEIRO, Mario L. R.; HUBSCHMAN, Jean Pierre; SARRAF, DavidPurpose: To describe the sequential evolution of outer retinal tubulations (ORTs) in patients diagnosed with choroidal neovascularization and/or retinal pigment epithelium atrophy. Methods: Retrospective evaluation of spectral domain optical coherence tomography of a consecutive cohort of patients with various retinal conditions. Results: We reviewed the clinical findings of 238 eyes of 119 consecutive patients (54 men and 65 women) with a mean age of 76.2 +/- 14.2 years (range: 57-90) and a mean follow-up of 3 +/- 1.6 years (range 1-7). Over the follow-up period, ORTs were diagnosed in 67 of 238 eyes (28.1%), 9 of which were imaged with sequential, eye-tracked spectral domain optical coherence tomography dating from the beginning of ORT formation. The presence of geographic atrophy and subretinal hyperreflective material at baseline were found to be risk factors for ORT development (P < 0.001 and P < 0.001, respectively). Outer retinal tubulations were divided into forming versus formed morphologies. The latter was comprised open and closed ORTs of which the open subtype was the most common. The formation of ORTs was significantly associated with microcystic macular lesions in the inner nuclear layer and the downward displacement of the outer plexiform layer, referred to as the outer plexiform layer subsidence sign (P < 0.001). Conclusion: Outer retinal tubulation is a frequent optical coherence tomography finding in eyes with choroidal neovascularization and geographic atrophy. Open ORTs with progressive scrolled edges and shortened diameter were significantly associated with microcystic macular lesions in the inner nuclear layer and the outer plexiform layer subsidence sign.
- ASSESSMENT OF THE DIFFERENCES IN PHARMACOKINETICS AND PHARMACODYNAMICS BETWEEN FOUR DISTINCT FORMULATIONS OF TRIAMCINOLONE ACETONIDE(2013) ZACHARIAS, Leandro C.; LIN, Ton; MIGON, Rafael; GHOSN, Corine; ORILLA, Werhner; FELDMANN, Barbara; RUIZ, Guadalupe; LI, Yong; BURKE, James; KUPPERMANN, Baruch D.Purpose: To compare the durability of Kenalog, Trivaris, Triesence, and compounding pharmacy preservative-free triamcinolone acetonide in pigmented rabbits with syneretic vitreous using direct visualization, pharmacodynamics, and pharmacokinetics. Methods: Twenty-five Dutch-belted rabbits were used. Pharmacokinetic experiment: Rabbits were intravitreally injected with one of four 4-mg triamcinolone acetonide formulations. Wide-field imaging was serially performed to document residual drug mass. Pharmacodynamics experiment: Four triamcinolone acetonide groups and one control group received intravitreal recombinant human vascular endothelial growth factor 165 every 2 weeks and were followed with fluorescein angiography to assess vascular endothelial growth factor retinal vasculopathy as a measure of residual steroid effect. Particle size of the formulations was measured with Mastersizer 2000. Results: Remaining triamcinolone acetonide mass after 19 weeks: 12,091 +/- 2,512 pixels for the Kenalog group, 1,307.36 +/- 695.57 for Trivaris, 5577 +/- 1477 for Triesence, and 1,535 +/- 329 for compounded preservative-free triamcinolone acetonide. Kenalog suppressed recombinant human vascular endothelial growth factor-induced retinopathy more effectively than the other triamcinolone acetonide groups at Week 39, the final time point assessed. Particle size (90th percentile) was 47 mu m for Kenalog, 26 mu m for Triesence, and 22 mu m for both compounded preservative-free triamcinolone acetonide and Trivaris. Conclusion: Triamcinolone acetonide formulations do not have the same pharmacokinetics/pharmacodynamics. Kenalog has the longest vitreous visibility and durability. Particle size appears to correlate with efficacy and durability. RETINA 33:522-531, 2013
- IN VITRO EVIDENCE FOR MYCOPHENOLIC ACID DOSE-RELATED CYTOTOXICITY IN HUMAN RETINAL CELLS(2013) ZACHARIAS, Leandro C.; DAMICO, Francisco Max; KENNEY, Maria C.; GASPARIN, Fabio; ACQUESTA, Felipe B.; VENTURA, Dora F.; TAKAHASHI, Walter Y.; KUPPERMANN, Baruch D.Purpose: Mycophenolic acid (MPA) is an immunosuppressive agent that controls noninfectious uveitis. Intravitreal MPA delivery may be a potential adjuvant therapy in patients who have to discontinue steroid or immunosuppressive systemic therapy because of side effects. The aims of this study are to evaluate the in vitro effects of MPA over human retinal pigment epithelium (ARPE-19) and human Muller cells (MIO M-1). Methods: ARPE-19 cells and MIO M-1 cells were exposed to 25, 50, and 100 mu g/mL of MPA (Roche Bioscience, Palo Alto, CA) for 24 hours. Toxicity was evaluated by trypan blue dye-exclusion cell viability assay, caspase-3/7 apoptosis-related assay, and JC-1 mitochondrial membrane potential assay. Results: The MPA (25 mu g/mL and 50 mu g/mL) did not cause reduction in cell viability or significant change in caspase-3/7 activity in both cell lines tested. Mycophenolic acid (100 mg/mL) caused a significant decrease in cell viability (P < 0.01) and higher caspase-3/7 activity (P < 0.05) in both cell lines compared with untreated cells. The JC-1 mitochondrial membrane potential did not show statistically significant differences for both cell lines and all concentration tested when compared with untreated controls (P > 0.05). Conclusion: Intraocular delivery may be a potential alternative for the treatment of noninfectious uveitis, either by intravitreal injection or sustained-release drug-delivery systems, in doses of 50 mu g/mL or lower.
- OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY BIOMARKERS AND MICROPERIMETRY FEATURES IN BEHÇET'S UVEITIS(2023) FERREIRA, Bruno F. A.; HIGASHI, Alex H.; PRADO, Leandro L.; GONCALVES, Celio R.; HADDAD, Maria A. O.; ZACHARIAS, Leandro C.; HIRATA, Carlos E.; YAMAMOTO, Joyce H.Purpose: To evaluate the parafoveal macular microvasculature and the macular function in patients with retinal vasculitis associated with Beh & ccedil;et's uveitis.Methods: In 14 patients with inactive Beh & ccedil;et's uveitis and 26 control individuals (13 with nonocular Beh & ccedil;et's syndrome and 13 healthy subjects), we analyzed the retinal nerve fiber layer, ganglion cell layer, full retinal thickness, foveal avascular zone area and sectorial parafoveal vascular density in the superficial vascular plexus, intermediate capillary plexus, and deep capillary plexus using SPECTRALIS optical coherence tomography (OCT) 2 and OCT angiography. Macular sensitivity was analyzed using an MP-3 microperimeter.Results: Eighteen eyes (78%) had a best-corrected visual acuity >= 20/25. Significant differences were found in Beh & ccedil;et's uveitis in comparison with the controls on the OCT and OCT angiography: 14.8%, 22.4%, and 14.9% ganglion cell layer thinning in the global, nasal, and inferior sectors, respectively; 6%, 13.2%, and 7.5% full retinal thickness thinning in the superior, nasal, and inferior sectors; and 16.8%, 14.9%, 23.6%, 15.8%, and 12.6% mean deep capillary plexus density reduction in the global, superior, nasal, inferior, and temporal sectors. Microperimetry data demonstrated significant mean reductions of 21% and 23.6% in central and average macular sensitivities and 28.8%, 40.4%, 27.7%, and 24.2% in the superior, nasal, inferior, and temporal sectors, respectively. Outer plexiform layer elevations were observed in Beh & ccedil;et's uveitis (69.6%).Conclusion: Beh & ccedil;et's uveitis presented structural and functional macular damage despite good best-corrected visual acuity, mainly affecting the nasal sector and the deep capillary plexus. On OCT and OCT angiography, quantitative and qualitative changes can be valuable biomarkers of ocular involvement in Beh & ccedil;et's syndrome.
- Novel Outer Retinal Optical Coherence Tomography Hyperreflective Abnormality Associated With Sub-Internal Limiting Membrane Hemorrhage(2015) SUZUKI, Ana Claudia F.; MIRANDA, Roger S.; ZACHARIAS, Leandro C.; MONTEIRO, Mario L. R.; TAKAHASHI, Walter Y.
- Intraoperative Infusion-related Jet Stream Enlargement of Macular Hole(2016) ZACHARIAS, Leandro C.; REZENDE, Flavio A.; SUZUKI, Ana Claudia F.; TANAKA, Tatiana; AZEVEDO, Breno Marques Da Silva; TAKAHASHI, Walter Y.