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Purpose To evaluate the retinal blood vascular network of the retinographies of patients with different grades of diabetic retinopathy. Methods Ninety Retinographies (MESSIDOR database) were used, with different grades of diabetic retinopathy divided into 4 groups: no retinopathy (n=23), grade one (n=20), grade two (n=20) and grade three (n=27) diabetic retinopathy. The grades of diabetic retinopathy were classified according to the number of microaneurysms, number of hemorrhages and the presence of neovascularization. The images were skeletonized and quantified by fractal methods: dimension of box-counting (Dbc) and information (Dinf). Results The means of Dbc values of groups were around 1.25, without statistically significant difference in the dimension values between groups for whole retina. There was also no statistical difference in Dinf values between groups, whose means ranged between 1.294 ± 0.013 (group of grade 1) and 1.3 ± 0.017 (group of grade 3). The retinographies were divided into regions of equal areas. The fractal values of some retinal regions showed statistical differences, but these differences were not enough to show the sensitivity of fractal methods in identifying diabetic retinopathy. Conclusion The fractal methods were not able to identify the different grades of diabetic retinopathy in retinographies. RESUMO Objetivo Avaliar a rede vascular sanguínea da retina a partir de retinografias de pacientes com diferentes graus de retinopatia diabética. Métodos Foram utilizadas 90 retinografias (banco de dados MESSIDOR), com diferentes graus de retinopatia diabética divididas em quatro grupos: sem retinopatia (n=23), retinopatia diabética de grau um (n=20), grau dois (n=20) e grau três (n=27). Os graus de retinopatia foram classificados conforme o número de microaneurismas, número de hemorragias e presença de neovascularização. As imagens foram esqueletizadas e quantificadas pelos métodos fractais: dimensão da contagem de caixas e informação. Resultados As médias dos valores das dimensões de contagem de caixas para todos os grupos foram próximas a 1,25, sem diferença estatisticamente significativa nos valores das dimensões entre os grupos para retina inteira. Também não houve diferença estatística nos valores da dimensão de informação entre os grupos, cujas médias variaram entre 1,294 ± 0,013 (grupo do grau 1) e 1,3 ± 0,017 (grupo do grau 3). As imagens retinianas foram divididas em regiões de áreas iguais. Os valores fractais de algumas regiões retinais mostraram diferenças estatísticas, mas estas não foram suficientes para mostrar a sensibilidade dos métodos fractais na identificação da retinopatia diabética. Conclusão Os métodos fractais não foram capazes de identificar os diferentes graus de retinopatia diabética em retinografias.

Animals developed or in an embryonic stage, are constantly subjected to magnetic pollution generated by electrical and electronic devices. Several researches have used the bird embryo as an experimental model to evaluate the action of magnetic field (MF) and electromagnetic field (EMF). This study proposed to perform a morphometric evaluation in the embryos and in the blood vascular network of the yolk sac membranes (YSM) of Japanese quail (

The brain is an organ rich in lipids, including cholesterol, in which these lipids are associated to structure and brain function. Thus alterations in lipid levels of diets may interfere in the brain electrical activity. Our aim was to evaluate the interference of hypercholesterolemic diets in the brain electrical activity in normal individuals and with epilepsy. Histological analysis and electrocorticograms (ECoG) were performed in animals fed with and without hypercholesterolemic diet before and during the status epilepticus induced by pilocarpine. The power spectrum of ECoG was used to estimate the contribution of different brain rhythms in ECoG signal. The animals submitted to the status epilepticus showed cell death, vacuolization with destructuration of the cell layers. Both animal groups, those with status epilepticus and status epilepticus with hypercholesterolemic diet, showed cellular lesions similar. The hyperlipid diet promoted increase of brain electrical activity, this was revealed by increase in the average power of beta wave (14-30 Hz) and decrease in the average power of the delta wave (0,5-4 Hz). This increase of brain electrical activity was even higher when the animals were fed a hypercholesterolemic diet and submitted to status epilepticus. Animals fed with hypercholesterolemic diet and submitted to status epilepticus presented a higher increase in brain excitability compared to control animals. We observed that hypercholesterolemic diet favored a greater severity of the status epilepticus.

Western diets are high in saturated fat and low in omega-3. Certain animals cannot produce omega-3 from their own lipids, making it necessary for it to be acquired from the diet. However, omega-3s are important components of the plasma membrane, and altering their proportions can promote physical and chemical alterations in the membranes, which may modify neuronal excitability. These alterations occur in healthy individuals, as well as in patients with epilepsy who are more sensitive to changes in brain electrical activity. This study evaluated the effect of a diet supplemented with omega-3 on the basal brain electrical activity both before and during status epilepticus in rats. To evaluate the brain electrical activity, we recorded electrocorticograms (ECoG) of animals both with and without omega-3 supplementation before and during status epilepticus induced by pilocarpine. Calculation of the average brain wave power by a power spectrum revealed that omega-3 supplementation reduced the average power of the delta wave by 20% and increased the average power of the beta wave by 45%. These effects were exacerbated when status epilepticus was induced in the animals supplemented with omega-3. The animals with and without omega-3 supplementation exhibited increases in basal brain electrical activities during status epilepticus. The two groups showed hyperactivity, but no significant difference between them was noted. Even though the brain activity levels observed during status epilepticus were similar between the two groups, neuron damage to the animals supplemented with omega-3 was more slight, revealing the neuroprotective effect of the omega-3.

O diabetes mellitus (DM) e atualmente a doenca que mais mata no mundo e o numero de pacientes aumenta a cada ano, devido ao modo de vida das populacoes nos diferentes paises, sendo os principais fatores que contribuem para este aumento o sedentarismo e a alimentacao de ma qualidade. O DM tipo 2 (DM2) e uma doenca na qual o paciente produz insulina em quantidade insuficiente ou possui resistencia a insulina, que se caracteriza pela nao absorcao da glicose pelas celulas. O diagnostico do DM2 geralmente e tardio e, algumas vezes, decorre das proprias complicacoes do diabetes. A literatura apresenta varios estudos que buscam verificar o envolvimento do DM2 sobre a atividade cerebral e consequentemente, sobre os processos de cognicao, tanto em humanos quanto em outras especies. Entretanto, nao ha trabalho na literatura que analise diretamente a influencia das oscilacoes de glicose, comuns aos pacientes com DM, sobre a atividade eletrica cortical. No presente trabalho, buscou-se verificar os efeitos do DM2, em modelo experimental, sobre os parâmetros da atividade eletrica cortical de ratos adultos machos. O eletrocorticograma (ECoG) dos animais foi usado para o registro da atividade eletrica cerebral. A analise desse sinal eletrofisiologico foi realizada pelos metodos do espectro de potencia, analise de flutuacao destendenciada (DFA) e dimensao fractal do espaco de fase reconstruido. Dez ratos Wistar machos de 60 dias foram subdivididos em dois grupos experimentais: um grupo controle (GC) e outro induzido ao DM2 (GD2) atraves da estreptozotocina. Os metodos matematicos de DFA e Analise fractal propostos foram sensiveis em detectar alteracoes no comportamento dos padroes eletrocorticograficos dos animais dos grupos experimentais causadas pelo diabetes somente quando aplicados em regioes especificas do espectro, porem quando aplicado ao ECoG total nao foram observadas alteracoes significativas.

Like heparan sulfate proteoglycans, some monosaccharides and glycosaminoglycans, such as sulfated glucosamine (GS) and chondroitin (CS), integrate the vascular extracellular matrix and may influence vascular endothelial cell growth. To assess the effects of these substances on blood vessel formation, we used the chick yolk sac membrane (YSM) model and fractal geometry quantification, which provided an objective in vivo method for testing potential agents that promote vasculogenesis and angiogenesis. An image processing method was developed to evaluate YSM capillary vessels after they were implanted in a methylcellulose disk of GS or CS at a concentration between 0.001–0.1 mg/disk (performed on 2-day old embryos). This method resulted in a binary image of the microvascular network (white vessels on a black background). Fractal box-counting (D BC ) and information (D INF ) dimensions were used to quantify the activity of GS and CS in vasculogenesis and angiogenesis. YSM treated with GS (0.001–0.1 mg) and CS (0.03–0.1 mg) showed an increase in fractal dimensions that corresponded to vitelline vessel growth compared to the control group (vehicle), with GS displaying higher fractal dimension values.

Objective: Target of this study was to test the capacity of chondroitin sulfate (CS) and glucosamine sulfate (GS) to induce in vivo angiogenesis. Methods: The proangiogenic activity of these compounds was analyzed through the assays in chorioallantoic membrane (CAM) of chick embryo and dorsal skin vascularization in mice, but before was realized a cell viability assay with human umbilical veins endothelial cells (HUVEC). Results: In the viability assay, concentrations tested between 30 and 3000 μg/ml showed a reduction of viable HUVEC number. In the CAM assay, CS and GS in an amount 2.0 mg/implant increased the vessels number as compared to control (phosphate buffered saline-PBS). In the assay of the dorsal skin vascularization of adult Swiss mice, the groups treated with CS (2 mg/implant; Gelfoam plug) exhibited an increase in the vessels number into plugs (0.52 ± 0.08 g/dl; measured as plug-hemoglobin content), a similar effect to that promoted by Fibroblast growth factor-2 (FGF-2; 50 ng/implant) (0.53 ± 0.1 g/dl). However the group treated with GS did not exhibit significant effect on mice skin vascularization. Conclusion: CS was capable to promote angiogenesis on CAM and dorsal skin vascularization, but GS only had pro-angiogenic activity in CAM vascular network.

Several studies have reported about the effects of magnetic fields (MFs) on vascular tissue. Extremely low frequency magnetic fields (ELF-MFs) can promote either inhibition or stimulation of vasculogenesis and angiogenesis, depending upon the intensity and time of exposure to the MF. To investigate the possible effects of ELF-MF on vascular processes, it is necessary to employ methods that allow parameterization of the vascular network. Vascular network is a structure with fractal geometry; therefore, fractal methods have been used to evaluate its morphometric complexity. Here, we used the lacunarity parameter (complementary method of fractal analysis) and multifractal analyses to investigate angiogenesis and vasculogenesis in the embryonic yolk sac membrane (YSM) of Japanese quails (Coturnix japonica) with and without exposure to an external MF of 1 mT and 60 Hz. Lacunarity results showed that the vascular density was lower for the group exposed to the magnetic field for 9 h/day. In addition, multifractal analysis showed reduced vascularization in the experimental groups (6 h/day and 9 h/day of exposure to MF). Furthermore, multifractal analysis showed difference between the groups exposed for 12 and 24 h/day. Using multifractal methods (generalized dimensions and singularity spectrum), it was possible to characterize the vascular network of the quail embryo YSM as a multifractal object, therefore proving this method to be a more appropriate application than the traditional monofractal methods.

Os biossurfactantes são moléculas com características tensoativas, isto é, tem o potencial de baixar a tensão superficial de líquidos, sendo indicados em diversas áreas de aplicação industrial e recuperação de derramamento de óleos em áreas afetadas. Através de atividades metabólicas, as bactérias e fungos sintetizam estes compostos anfipáticos na fase exponencial de crescimento microbiano, liberando moléculas com propriedades especificas de acordo com o tipo de substrato. Assim, busca-se alternativas e processos biotecnológicos que alcancem bons rendimentos e baixo custo na obtenção dos biossurfactantes. Com essa finalidade são utilizados óleos vegetais, óleos residuais de frituras e resíduos agroindustriais que apresentam características peculiares importantes para produção destas moléculas. Atualmente mais de 80% dos produtos de limpeza são fabricados com surfactantes sintéticos derivados do petróleo. O objetivo deste artigo foi destacar os aspectos relacionados na produção dos surfactantes de origem biológica e a importância destes para serem empregados no mercado industrial.

Magnetic fields (MF) can alter the dynamic behavior of vascular tissue and may have a stimulatory or inhibitory effect on blood vessel growth. Fractal geometry has been used in several studies as a tool to describe the development of blood vascular networks. Due to its self-similarity, irregularity, fractional dimension, and dependence on the scale of vessel dimensions, vascular networks can be taken as fractal objects. In this work, we calculated the fractal dimension by the methods of box counting (D(bc)) and information dimension (D(inf)) to evaluate the development of blood vessels of the yolk sac membrane (YSM) from quail embryos exposed to MF with a magnetic flux density of 1 mT and a frequency of 60 Hz. The obtained results showed that when the MF was applied to embryos aged between 48 and 72 h, in sessions of 2 h (6 h/day) and 3 h (9 h/day) with exposure intervals between 6 and 5 h, respectively, blood vascular formation was inhibited. Exposure sessions shorter than 2 h or longer than 3 h had no observable change on the vascular process. In contrast, the magnetic field had no observable change on the YSM vascular network for embryos aged between 72 and 96 h, irrespective of the exposure time. In conclusion, these results show a "window effect" regarding exposure time.