Retinal Pigmented Epithelial Cells Cytotoxicity and Apoptosis through Activation of the Mitochondrial Intrinsic Pathway: Role of Indocyanine Green, Brilliant Blue and Implications for Chromovitrectomy

Purpose: To investigate the in vitro effect of four vital dyes on toxicity and apoptosis in a human retinal pigment epithelial (RPE) cell line.Methods: ARPE-19 cells were exposed to brilliant blue (BriB), methyl blue (MetB), acid violet (AcV) and indocyanine green (ICG). Balanced salt solution was used as control. Five different concentrations of each dye (1, 0.5, 0.25, 0.05 and 0.005 mg/mL) and two exposure times (3 and 30 min) were tested. Cell viability was determined by cell count and MTS assay and cell toxicity by LDH assay. Real-time PCR and Western blotting were used to access the apoptosis process.Results: ICG significantly reduced cell viability after 3 minutes of exposure at all concentrations (p < 0.01). BriB was safe at concentrations up to 0.25 mg/mL and MetB at concentrations up to 0.5 mg/mL, while AcV was safe up to 0.05 mg/ml, after 3 minutes of exposure. Toxicity was higher, when the cells were treated for 30 minutes. Expression of Bax, cytochrome c and caspase-9 was upregulated at the mRNA and protein level after ICG exposure, while Bcl-2 was downregulated. AcV and MetB were similar to control. However, BriB resulted in upregulation of Bcl-2, an antiapoptotic protein.Conclusions: the safest dye used on RPE cells was MetB followed by BriB and AcV. ICG was toxic at all concentrations and exposure times tested. Moreover, ICG was the only dye that induced apoptosis in ARPE-19 cells. BriB significantly increased Bcl-2 protein levels, which might protect against the apoptosis process.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)National Institutes of Health CenterResearch to Prevent BlindnessDepartment of Defense (DOD)Universidade Federal de São Paulo, Inst Visao IPEPO, Dept Oftalmol, São Paulo, BrazilUniv Miami, Bascom Palmer Eye Inst, Miami, FL USAUniversidade Federal de São Paulo, Inst Visao IPEPO, Dept Oftalmol, São Paulo, BrazilNational Institutes of Health Center: P30EY014801Department of Defense (DOD): W81XWH-09-1-0675Web of Scienc

Obesity‐induced diabetes and lower urinary tract fibrosis promote urinary voiding dysfunction in a mouse model

BACKGROUND Progressive aging‐ and inflammation‐associated fibrosis effectively remodels the extracellular matrix (ECM) to increase prostate tissue stiffness and reduce urethral flexibility, resulting in urinary flow obstruction and lower urinary tract symptoms (LUTS). In the current study, we sought to test whether senescence‐accelerated mouse prone (SAMP)6 mice, which were reported to develop prostatic fibrosis, would also develop LUTS, and whether these symptoms would be exacerbated by diet‐induced obesity and concurrent Type 2 Diabetes Mellitus (T2DM). METHODS To accomplish this, SAMP6 and AKR/J background strain mice were fed regular mouse chow, low fat diet chow, or high fat diet chow for 8 months, then subjected to glucose tolerance tests, assessed for plasma insulin levels, evaluated for urinary voiding function, and assessed for lower urinary tract fibrosis. RESULTS The results of these studies show that SAMP6 mice and AKR/J background strain mice develop diet‐induced obesity and T2DM concurrent with urinary voiding dysfunction. Moreover, urinary voiding dysfunction was more severe in SAMP6 than AKR/J mice and was associated with pronounced prostatic and urethral tissue fibrosis. CONCLUSIONS Taken together, these studies suggest that obesity, T2DM, lower urinary tract fibrosis, and urinary voiding dysfunction are inextricably and biologically linked. Prostate 73: 1123–1133, 2013. © 2013 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98367/1/22662_ftp.pd

Star formation in dense clusters

A model of core-clump accretion with equally likely stopping describes star formation in the dense parts of clusters, where models of isolated collapsing cores may not apply. Each core accretes at a constant rate onto its protostar, while the surrounding clump gas accretes as a power of protostar mass. Short accretion flows resemble Shu accretion, and make low-mass stars. Long flows resemble reduced Bondi accretion and make massive stars. Accretion stops due to environmental processes of dynamical ejection, gravitational competition, and gas dispersal by stellar feedback, independent of initial core structure. The model matches the field star IMF from 0.01 to more than 10 solar masses. The core accretion rate and the mean accretion duration set the peak of the IMF, independent of the local Jeans mass. Massive protostars require the longest accretion durations, up to 0.5 Myr. The maximum protostar luminosity in a cluster indicates the mass and age of its oldest protostar. The distribution of protostar luminosities matches those in active star-forming regions if protostars have a constant birthrate but not if their births are coeval. For constant birthrate, the ratio of YSOs to protostars indicates the star-forming age of a cluster, typically ~1 Myr. The protostar accretion luminosity is typically less than its steady spherical value by a factor of ~2, consistent with models of episodic disk accretion.Comment: accepted for publication by Astrophysical Journa

Classification and monitoring of urbanized areas using computer vision techniques

In this paper we propose a computer vision system to classify permeable and impermeable areas of a bounded area for study including the Micro-basin of Segredo and adjacent micro-basins, located in the municipality of Campo Grande/MS, Brazil, in order to evaluate the increase in urban density between the years 2008 and 2016. The proposed system is based on the image segmentation method Simple Linear Iterative Clustering (SLIC) to partition an image into multiple segments and generate superpixels that differentiate the permeable and impermeable areas; and attribute extraction algorithms to describe the visual features such as color, gradient, texture, and shape. The performance of five supervised learning methods was evaluated for the task of permeable and impermeable areas recognition. The proposed approach achieved an accuracy of 94.6% using the Support Vector Machine (SVM) algorithm. In addition, the results showed an increase of 7.2% in the urban occupation rate of the study area between the analyzed years. The results indicate that the proposed approach can support specialists and managers in the monitoring of urban density and its environmental impact.Neste artigo propomos um sistema de visão computacional para classificar áreas permeáveis e impermeáveis de uma região delimitada para estudo compreendendo a Microbacia do Segredo e microbacias adjacentes, localizada no município de Campo Grande/MS, Brasil, a fim de avaliar o aumento do adensamento urbano entre os anos de 2008 e 2016. O sistema proposto baseia-se no método de segmentação de imagens Simple Linear Iterative Clustering (SLIC) para particionar uma imagem em múltiplos segmentos e gerar superpixels que diferenciem as áreas permeáveis e impermeáveis; e algoritmos de extração de atributos para descrever as características visuais, como cor, gradiente, textura e forma. O desempenho de cinco métodos de aprendizado supervisionados foi avaliado para a tarefa de reconhecimento de áreas permeáveis e impermeáveis. A abordagem proposta atingiu uma acurácia de 94,6% usando o algoritmo Support Vector Machine (SVM). Além disso, os resultados mostraram um aumento de 7,2% na taxa de ocupação urbana da área de estudo entre os anos analisados. Os resultados indicam que a abordagem proposta pode apoiar especialistas e gestores no monitoramento do adensamento urbano e o seu impacto ambiental

Reconstructing Native American Population History

The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved1–5. One contentious issue is whether the settlement occurred via a single6–8 or multiple streams of migration from Siberia9–15. The pattern of dispersals within the Americas is also poorly understood. To address these questions at higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. We show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call “First American”. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan-speakers on both sides of the Panama Isthmus, who have ancestry from both North and South America