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Purpose Based on our preview evidence that reduced nuclear content of the transcription factor Myc-associated protein X (MAX) is an early event associated with degeneration of retinal ganglion cells (RGCs), in the present study, our purpose was to test whether the overexpression of human MAX had a neuroprotective effect against RGC injury. Methods Overexpression of either MAX or green fluorescent protein (GFP) in the retina was achieved by intravitreal injections of recombinant adenovirus-associated viruses (rAAVs). Lister Hooded rats were used in three models of RGC degeneration: (1) cultures of retinal explants for 30 hours ex vivo from the eyes of 14-day-old rats that had received intravitreal injections of rAAV2- MAX or the control vector rAAV2- GFP at birth; (2) an optic nerve crush model, in which 1-month-old rats received intravitreal injection of either rAAV2- MAX or rAAV2- GFP and, 4 weeks later, were operated on; and (3) an ocular hypertension (OHT) glaucoma model, in which 1-month-old rats received intravitreal injection of either rAAV2- MAX or rAAV2- GFP and, 4 weeks later, were subject to cauterization of the limbal plexus. Cell death was estimated by detection of pyknotic nuclei and TUNEL technique and correlated with MAX immunocontent in an ex vivo model of retinal explants. MAX expression was detected by quantitative RT-PCR. In the OHT model, survival of RGCs was quantified by retrograde labeling with DiI or immunostaining for BRN3a at 14 days after in vivo injury. Functional integrity of RGCs was analyzed through pattern electroretinography, and damage to the optic nerve was examined in semithin sections. Results In all three models of RGC insult, gene therapy by overexpression of MAX prevented RGC death. Also, ON degeneration and electrophysiologic deficits were prevented in the OHT model. Conclusions Our experiments offer proof of concept for a novel neuroprotective gene therapy for glaucomatous neurodegeneration based on overexpression of MAX.

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Wind power has grown popular in past recent years due to environmental issues and the search for alternative energy sources. Thus, the viability for wind power generation projects must be studied in order to attend to the environmental concerns and still be attractive and profitable. Therefore, this article aims to perform a sensitive analysis in order to identify the variables that influence most in the viability of a wind power investment for small size companies in the Brazilian northeast. For this, a stochastic analysis of viability through Monte Carlo Simulation (MCS) will be made and afterwards, Artificial Neural Networks (ANN) models will be applied for the most relevant variables identification. Through the sensitivity, it appears that the most relevant factors in the analysis are the speed of wind, energy tariff and the investment amount. Thus, the viability of the investment is straightly tied to the region where the wind turbine is installed, and the government incentives may allow decreasing in the investment amount for wind power. Based on this, incentives programs for the production of clean energy include cheaper purchase of wind turbines, lower taxing and financing rates, can make wind power more profitable and attractive.

Glaucoma is a neurodegenerative disorder characterized by the progressive functional impairment and degeneration of the retinal ganglion cells (RGCs) and their axons, and is the leading cause of irreversible blindness worldwide. Current management of glaucoma is based on reduction of high intraocular pressure (IOP), one of its most consistent risk factors, but the disease proceeds in almost half of the patients despite such treatments. Several experimental models of glaucoma have been developed in rodents, most of which present shortcomings such as high surgical invasiveness, slow learning curves, damage to the transparency of the optic media which prevents adequate functional assessment, and variable results. Here we describe a novel and simple method to induce ocular hypertension in pigmented rats, based on low-temperature cauterization of the whole circumference of the limbal vascular plexus, a major component of aqueous humor drainage and easily accessible for surgical procedures. This simple, low-cost and efficient method produced a reproducible subacute ocular hypertension with full clinical recovery, followed by a steady loss of retinal ganglion cells and optic axons, accompanied by functional changes detected both by electrophysiological and behavioral methods.