Methylmercury intoxication activates nitric oxide synthase in chick retinal cell culture

The visual system is a potential target for methylmercury (MeHg) intoxication. Nevertheless, there are few studies about the cellular mechanisms of toxicity induced by MeHg in retinal cells. Various reports have indicated a critical role for nitric oxide synthase (NOS) activation in modulating MeHg neurotoxicity in cerebellar and cortical regions. The aim of the present study is to describe the effects of MeHg on cell viability and NOS activation in chick retinal cell cultures. For this purpose, primary cultures were prepared from 7-day-old chick embryos: retinas were aseptically dissected and dissociated and cells were grown at 37ºC for 7-8 days. Cultures were exposed to MeHg (10 µM, 100 µM, and 1 mM) for 2, 4, and 6 h. Cell viability was measured by MTT method and NOS activity by monitoring the conversion of L-[H3]-arginine to L-[H3]-citrulline. The incubation of cultured retina cells with 10 and 100 µM MeHg promoted an increase of NOS activity compared to control (P < 0.05). Maximum values (P < 0.05) were reached after 4 h of MeHg incubation: increases of 81.6 ± 5.3 and 91.3 ± 3.7%, respectively (data are reported as mean ± SEM for 4 replicates). MeHg also promoted a concentration- and time-dependent decrease in cell viability, with the highest toxicity (a reduction of about 80% in cell viability) being observed at the concentration of 1 mM and after 4-6 h of incubation. The present study demonstrates for the first time the modulation of MeHg neurotoxicity in retinal cells by the nitrergic system

Inherited hemoglobin disorders in an Afro-Amazonian community: Saracura

ABSTRACT: The most common hemoglobinopathies, viz, hemoglobins S and C, and α-and β-thalassemias, were investigated through the molecular screening of 116 subjects from the community of Saracura, comprising fugitive African slaves from farms of the municipality of Santarém, in the west of Pará State, Brazilian Amazon. The observed frequency of the HBB*S gene (0.9%) was significantly lower than that encountered in other Afro-derived communities in the region. Concomitantly, the absence of the HBB*C allele has been reported for most of the Afro-Amazonian communities thus far studied. As remnant populations of quilombos are generally small, the heterogeneous distribution of HBB*S and HBB*C alleles among them is probably due to genetic drift and/or founder effect. The observed frequency of 3.7 kb deletion in Saracura (8.5%) was consistent with the African origin of the population, with a certain degree of local differentiation and admixture with individuals of Caucasian ancestry, placed in evidence by the occurrence of - -(MED) deletion (1.2%), a common mutation in Mediterranean regions. As regards f-thalassemia, among the seven different mutations found in Saracura, three βºand two β+ mutations were of Mediterranean origin, and two β+ of African. Thus, only 28% of the local β-thalassemia mutations found in Saracura were of African origin.

Cytogenetic damage related to low levels of methyl mercury contamination in the Brazilian Amazon

The mercury rejected in the water system, from mining operations and lixiviation of soils after deforestation, is considered to be the main contributors to the contamination of the ecosystem in the Amazon Basin. The objectives of the present study were to examine cytogenetic functions in peripheral lymphocytes within a population living on the banks of the Tapajós River with respect to methylmercury (MeHg) contamination, using hair mercury as a biological indicator of exposure. Our investigation shows a clear relation between methylmercury contamination and cytogenetic damage in lymphocytes at levels well below 50 micrograms/gram, the level at which initial clinical signs and symptoms of mercury poisoning occur. The first apparent biological effect with increasing MeHg hair level was the impairment of lymphocyte proliferation measured as mitotic index (MI). The relation between mercury concentration in hair and MI suggests that this parameter, an indicator of changes in lymphocytes and their ability to respond to culture conditions, may be an early marker of cytotoxicity and genotoxicity in humans and should be taken into account in the preliminary evaluation of the risks to populations exposed in vivo. This is the first report showing clear cytotoxic effects of long-term exposure to MeHg. Although the results strongly suggest that, under the conditions examined here, MeHg is both a spindle poison and a clastogen, the biological significance of these observations are as yet unknown. A long-term follow-up of these subjects should be undertaken.

Karyotypic analysis in species of the genus Dasyprocta (Rodentia: Dasyproctidae) found in Brazilian Amazon

Foram estudados citogeneticamente um total de 30 animais das espécies D. prymnolopha (N=20), D. leporina (N=6), D. fuliginosa (N=1) e Dasyprocta sp. (N=3) (Dasyproctidae, Histricognathi). As preparações cromossômicas foram obtidas do cultivo de sangue periférico, além de medula óssea e baço em D. prymnolopha e D. leporina. O número diplóide foi de 64/65 em todos os exemplares. O cariótipo mostrou similaridade, não sendo detectado, através de coloração convencional de giemsa e de banda G, polimorfismo cromossômico em qualquer uma das espécies estudadas. A distribuição da heterocromatina constitutiva na região pericentromérica de todos os cromossomos foi similar nas quatro espécies. D. prymnolopha, D. leporina e Dasyprocta sp. apresentaram variação no tamanho do bloco heterocromático em um dos homólogos do par A18. D. fuliginosa apresentou a heterocromatina uniformemente distribuída em todos os cromossomos. Não houve variação no padrão das RONs entre as espécies estudadas.

Movimento Hip Hop paulistano: a produção artística dos racionais MC's

Pós-graduação em Letras - IBILCE

Effects of some parameters in upscale culture of Haematococcus pluvialis Flotow

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O fazer saber das danças afro: investigando matrizes negras em movimento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Greening the campus of a Brazilian university: cultural challenges

Purpose - This study examined the relationship between environmental management practices developed at a campus of a Brazilian university (University of Sao Paulo) and the greening of its organizational culture. The paper aims to discuss these issues.Design/methodology/approach - This article presents a theoretical background based on the concepts of environmental management, organizational culture and environmental management in higher education institutions. The main framework of this research is the model proposed by Harris and Crane.Findings - The studied university has an environmental management program that is sometimes constrained in the following ways: the university bureaucracy and hierarchy; the main performance indicators for lecturers and professors are based on scientific production and publication, giving them little time for complementary activities; and some units develop their own environmental management practices, but they are not disseminated as best practices for use by other units. Some academic units showcase the proactive actions of professors who incorporate environmental management into their daily activities. The general perception is that the phrase environmental management is almost synonymous with solid waste management.Originality/value - This research details the first Brazilian application of the Harris and Crane model. It contributes an original analysis of environmental management and green organizational culture of a Brazilian university, an organizational type that has seldom been studied to date.

Lethal effect of high concentrations of Parecoxib and Flunixin meglumine on the in vitro culture of bovine embryos

Since cyclooxygenase (COX) inhibitors have been pointed out as potential treatments to increase pregnancy rates after embryo transfer, the present experiment aimed to evaluate the effects of flunixin meglumine (FM) and parecoxib (P), a COX-1 and 2 or COX-2 specific inhibitor, respectively, on the development of bovine embryos until the hatched blastocyst stage. In vitro produced bovine embryos were cultured in media with different concentrations of FM (0.14; 1.4; 14; 140 or 1400 mu g/ml) or P (0.09; 0.9; 9; 90 or 900 mu g/ml) and the production rates were evaluated. Concentrations of FM <= 14 mu g/ml and P <= 90 mu g/ml did not impair embryo development, although compiled data from non-lethal FM concentrations (<= 14 mu g/ml) indicated a toxic effect enough to decrease the hatching rate of blastocysts. Concentrations of FM at 140 and 1400 mu g/ml and P at 900 mu g/ml were lethal as no cleavage was detected on presumptive zygotes.

Dilemas na tradução de Muse & Drudge (Musa E Mula), de Harryette Mullen: negritude, dissonância e miscigenação

This paper aims to discuss a project of translating part of the work Muse & Drudge, by the award-winning African-American poet Harryette Mullen, into Brazilian Portuguese, with focus on a single poem. In Muse & Drudge Mullen combines cultural critique with humor, lyricism and punning, which has unfolded the frontiers between cultural and racial identity, and has put into question the opposition between popular and high culture. This work analyzes to which extent the proposed translation produces a new set of intertextual relations that might culminate in “unexpected” meanings. It is a goal to understand how the effects of such “unexpected” meanings reveal the “encounter” between the so-called racial “black/white” dichotomy, predominant in the US culture, and the notion of “miscegenation” and “racial democracy” in Brazil.

O papel da tradução na construção da identidade da literatura afro-americana no Brasill

This paper discusses the role of translation in the construction of the identity of African-American literature in Brazil, by considering the relations between the Brazilian sociocultural context, infl uenced by biological and cultural miscegenation, and the particular way that the literary criticism represented by essays and translations of the Brazilian critic Sergio Milliet, published in between the 40’s and 60’s, approaches AfricanAmerican poetry, with special focus on Langston Hughes’ poems. In this paper, differences between Brazilian and American racial contexts are brought into light in regard to the discourses on miscegenation and race. It is discussed the extent to which Sergio Milliet developed a racialized identity for African-American poetry in his essays, which, however, was rebuilt through translation, in his anthology Obras Primas da Poesia Universal, with a less racialized perspective so that African-American aesthetics could sound less dissonant and regional and more inclined towards the principle of universality which characterizes the anthology composed of renowned foreign and Brazilian poets.

Leuconostoc mesenteroides SJRP55: a bacteriocinogenic strain isolated from Brazilian water buffalo mozzarella cheese

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Intervenção pedagógica e construção de noções étnicas por meio da pesquisa escolar: um estudo piagetiano

Pós-graduação em Educação - FFC

Improvement of submerged culture conditions to produce colorants by Penicillium purpurogenum

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fish immunology: the modification and manipulation of the innate immune system: Brazilian studies

The understanding of fish immune system structure and function is essential for the development of new technologies and products to improve productivity. This is the first review on immune system of fish with Brazilian studies. Aquaculture in Brazil has shown massive growth in recent years due to methods of culture intensification. However, these procedures led to disease outbreaks, as well as the chemotherapy and the misuse of antibiotics. A viable alternative to avoid the use of chemicals and prevent economic losses is the administration of immunostimulants and prebiotcs, which act by increasing the innate immune system. In Brazil there is a lack of studies on fish immune system, except by some groups that have studied the effects of the immunostimulants administration in various species.