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Introduction: This study aimed to describe the quantitative features of the microvasculature in the cystic lesions of branch retinal vein occlusion (BRVO). Methods: A total of 43 eyes with BRVO, treated with anti-vascular endothelial growth factor therapy, were analyzed. Using wide-field swept-source optical coherence tomography angiography (OCTA), en face OCT images were obtained by depth-integrated reflectivity of the retina, and vascular density (VD), vascular length (VL), vascular lacunarity, and fractal dimension (FD) were evaluated in a 12 × 12-mm area of retinal nonperfusion. Results: The mean area of affected lesions was 38.7 ± 19.8 mm2, and cystic lesions were 8.5 ± 10.1 mm2. VD, VL, and FD were significantly decreased in the cystic lesions compared to other affected lesions in the same eyes (p = 0.0010, p = 0.0001, and p = 0.0003, respectively) and in all eyes (p = 0.0281, p = 0.0050, and p < 0.0001, respectively). VD in cystic lesions within the vascular arcade (25 eyes) correlated with best-corrected visual acuity on OCTA (r = -0.433, and p = 0.0492). Conclusions: Vascular structure in the cystic lesions was unpreserved compared to the other lesions in BRVO. These findings may help in understanding the pathophysiology of retinal edema in BRVO.
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BACKGROUND/AIMS: To investigate the chronological corneal changes associated with long-term rigid gas-permeable contact lens (RGP-CL) wear in patients with keratoconus (KC). METHODS: Clinical records of 405 patients with KC or with KC suspect were retrospectively reviewed. Patients with mild-to-moderate KC and uneventful follow-up were classified into the CL (RGP-CL wear) and non-CL (without CL wear) groups. Inclusion criteria were (1) at least 3-year follow-up and (2) Scheimpflug-based corneal imaging examination at each visit. The anterior (ARC) and posterior (PRC) radius of curvature obtained in a 3.0 mm optical zone, the thinnest pachymetry reading of the corneal thickness (Tmin), and maximum keratometry values (Kmax) were investigated as tomographic parameters. RESULTS: Twenty-two and 15 patients who met the inclusion criteria were included in the CL and non-CL groups, respectively (31 and 20 eyes, respectively). The mean observation periods were 75 (CL group) and 63 (non-CL group) months. A multivariable non-linear regression analysis to assess the change in tomographic parameters over the follow-up period and difference of the trend between the two groups demonstrated no significant differences in the chronological change in ARC, PRC and Tmin between the CL and non-CL groups (p=0.318, p=0.280 and p=0.874, respectively). CONCLUSION: Based on corneal tomographic evaluation over 5-6 years, the effects of long-term RGP-CL wear had no effect on KC progression.
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Lentes de Contato , Córnea/patologia , Ceratocone/diagnóstico , Ceratocone/terapia , Adolescente , Adulto , Topografia da Córnea , Progressão da Doença , Feminino , Seguimentos , Humanos , Ceratocone/fisiopatologia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Ajuste de Prótese , Estudos Retrospectivos , Inquéritos e Questionários , Acuidade Visual/fisiologia , Adulto JovemRESUMO
We have used protein engineering to expand the palette of genetically encoded calcium ion (Ca(2+)) indicators to include orange and improved red fluorescent variants, and validated the latter for combined use with optogenetic activation by channelrhodopsin-2 (ChR2). These indicators feature intensiometric signal changes that are 1.7- to 9.7-fold improved relatively to the progenitor Ca(2+) indicator, R-GECO1. In the course of this work, we discovered a photoactivation phenomenon in red fluorescent Ca(2+) indicators that, if not appreciated and accounted for, can cause false-positive artifacts in Ca(2+) imaging traces during optogenetic activation with ChR2. We demonstrate, in both a beta cell line and slice culture of developing mouse neocortex, that these artifacts can be avoided by using an appropriately low intensity of blue light for ChR2 activation.
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Cálcio/metabolismo , Optogenética/métodos , Processos Fotoquímicos , Engenharia de Proteínas/métodos , Animais , Córtex Cerebral/química , Córtex Cerebral/metabolismo , Channelrhodopsins , Células HEK293 , Células HeLa , Humanos , Indicadores e Reagentes/metabolismo , Camundongos , Técnicas de Cultura de Órgãos , Estrutura Secundária de Proteína , Peixe-ZebraRESUMO
Engineered fluorescent protein (FP) chimeras that modulate their fluorescence in response to changes in calcium ion (Ca(2+)) concentration are powerful tools for visualizing intracellular signaling activity. However, despite a decade of availability, the palette of single FP-based Ca(2+) indicators has remained limited to a single green hue. We have expanded this palette by developing blue, improved green, and red intensiometric indicators, as well as an emission ratiometric indicator with an 11,000% ratio change. This series enables improved single-color Ca(2+) imaging in neurons and transgenic Caenorhabditis elegans. In HeLa cells, Ca(2+) was imaged in three subcellular compartments, and, in conjunction with a cyan FP-yellow FP-based indicator, Ca(2+) and adenosine 5'-triphosphate were simultaneously imaged. This palette of indicators paints the way to a colorful new era of Ca(2+) imaging.