Relaxation of thoracic aorta and pulmonary artery rings of marmosets (Callithrix spp.) by endothelium-derived 6-nitrodopamine.

6-Nitrodopamine is a novel catecholamine released by vascular tissues, heart, and vas deferens. The aim of this study was to investigate whether 6-nitrodopamine is released from the thoracic aorta and pulmonary artery rings of marmosets (Callithrix spp.) and to evaluate the relaxing and anti-contractile actions of this catecholamine. Release of 6-nitrodopamine, dopamine, noradrenaline, and adrenaline was assessed by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The relaxations induced by 6-nitrodopamine and by the selective dopamine D2 receptor antagonist L-741,626 were evaluated on U-46619 (3 nM)-pre-contracted vessels. The effects of 6-nitrodopamine and L-741,626 on the contractions induced by electric-field stimulation (EFS), dopamine, noradrenaline, and adrenaline were also investigated. Both aorta and pulmonary artery rings exhibited endothelium-dependent release of 6-nitrodopamine, which was significantly reduced by the NO synthesis inhibitor L-NAME. Addition of 6-nitrodopamine or L-741,626 caused concentration-dependent relaxations of both vascular tissues, which were almost abolished by endothelium removal, whereas L-NAME and the soluble guanylate cyclase inhibitor ODQ had no effect on 6-nitrodopamine-induced relaxations. Additionally, pre-incubation with 6-nitrodopamine antagonized the dopamine-induced contractions, without affecting the noradrenaline- and adrenaline-induced contractions. Pre-incubation with L-741,626 antagonized the contractions induced by all catecholamines. The EFS-induced contractions were significantly increased by L-NAME, but unaffected by ODQ. Immunohistochemical assays showed no immunostaining of the neural tissue markers S-100 and calretinin in either vascular tissue. The results indicated that 6-nitrodopamine is the major catecholamine released by marmoset vascular tissues, and it acts as a potent and selective antagonist of dopamine D2-like receptors. 6-nitrodopamine release may be the major mechanism by which NO causes vasodilatation.

Relaxation of thoracic aorta and pulmonary artery rings of marmosets (Callithrix spp.) by endothelium-derived 6-nitrodopamine

6-Nitrodopamine is a novel catecholamine released by vascular tissues, heart, and vas deferens. The aim of this study was to investigate whether 6-nitrodopamine is released from the thoracic aorta and pulmonary artery rings of marmosets (Callithrix spp.) and to evaluate the relaxing and anti-contractile actions of this catecholamine. Release of 6-nitrodopamine, dopamine, noradrenaline, and adrenaline was assessed by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The relaxations induced by 6-nitrodopamine and by the selective dopamine D2 receptor antagonist L-741,626 were evaluated on U-46619 (3 nM)-pre-contracted vessels. The effects of 6-nitrodopamine and L-741,626 on the contractions induced by electric-field stimulation (EFS), dopamine, noradrenaline, and adrenaline were also investigated. Both aorta and pulmonary artery rings exhibited endothelium-dependent release of 6-nitrodopamine, which was significantly reduced by the NO synthesis inhibitor L-NAME. Addition of 6-nitrodopamine or L-741,626 caused concentration-dependent relaxations of both vascular tissues, which were almost abolished by endothelium removal, whereas L-NAME and the soluble guanylate cyclase inhibitor ODQ had no effect on 6-nitrodopamine-induced relaxations. Additionally, pre-incubation with 6-nitrodopamine antagonized the dopamine-induced contractions, without affecting the noradrenaline- and adrenaline-induced contractions. Pre-incubation with L-741,626 antagonized the contractions induced by all catecholamines. The EFS-induced contractions were significantly increased by L-NAME, but unaffected by ODQ. Immunohistochemical assays showed no immunostaining of the neural tissue markers S-100 and calretinin in either vascular tissue. The results indicated that 6-nitrodopamine is the major catecholamine released by marmoset vascular tissues, and it acts as a potent and selective antagonist of dopamine D2-like receptors. 6-nitrodopamine release may be the major mechanism by which NO causes vasodilatation.

Can severe drought periods increase metal concentrations in mangrove sediments? A case study in eastern Brazil.

Mangrove ecosystems are essential to society, providing ecological and economic services, and play a crucial role in the geochemical land-ocean interface as a sink for potentially toxic metals. This study assessed metals (Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn) and arsenic in sediments from three mangrove zones (Tidal Flat, Rhizophora mangle L. and Avicennia schaueriana Stapf & Leechman ex Moldenke forests) during two seasons: spring of 2015 and autumn of 2016, with the latter being a severe drought year. Overall results suggest that Fe/Mn oxyhydroxides and clay minerals control the distribution of metal and arsenic in the Tidal Flat zone. In the mangrove forest however, sulfur and organic matter dominate complexation, with Fe mainly present as insoluble sulfide, and As, Cd, Cu and Zn as metal sulfides or organometallic complexes. In the autumn of 2016, all elements except Cd and Pb had lower concentrations compared to the spring of 2015. Cd and Pb were probably transferred from sources other than mangrove sediments, due to increased saline water intrusion, a consequence of reduced riverine flow, and precipitated in the Rhizophora mangle and Avicennia schaueriana mangrove forests. This increase of Cd and Pb in the mangrove forest suggests potential storage of metal contaminants in the organic rich areas, a change in availability and potential toxicity to fauna and flora and a need for regulatory responses to sediment quality. These results indicate a change in sediment metal contaminant dynamics with the increasing occurrence of extreme weather events - an increased risk to the ecosystem.

Emission rates of nitrogen and phosphorus in a tropical coastal river basin: a strategic management approach.

Watershed studies that account for nutrient loadings are crucial for suitable river basin and estuarine management. This study aims to contribute to the environmental planning and decision making regarding nitrogen and phosphorus loadings for the watershed of the Vitória Bay Estuarine System (VBES; 1925 km2) in southeast Brazil. Here, we estimate that the VBES had annual loadings (in 2016) from ten tributary river basins of 5480 and 10,784 t for P and N, respectively, based on emission factors for natural and anthropogenic sources. The main contribution sources were related to livestock farming (4801 t of P and 8000 t of N) and domestic wastewater (492 t of P and 1706 t of N). However, urban loadings have higher expressions when considering the input by watershed area (0.25 and 0.87 t km-2 year-1 of P and N yields, respectively), which are mainly due to wastewater since 70% of the sewage is untreated. Urban emissions play a prominent role and have a tendency to be aggravated due to Brazilian population growth (0.8% annual rate). If the current wastewater emissions continue, P and N loadings will likely increase by 1.316% to totals of 713 and 2474 t year-1 in 2050 for P and N, respectively. Considering that the wastewater tertiary treatment cost is US$ 0.50 m-3, and that in the future 70% of all wastewater will be collected, the P and N loadings will drop to 18.4 and 424.1 t year-1, respectively, with a treatment cost of 25 million USD year-1. The model holds well for non-regulated watersheds. However, for regulated basins, such as the Santa Maria de Vitória, the model overestimates the loadings mainly due to the damming systems in these watersheds (accounting for 49% retention of P and 0.13% retention of N).

Environmental Electrokinetics for a sustainable subsurface.

Soil and groundwater are key components in the sustainable management of the subsurface environment. Source contamination is one of its main threats and is commonly addressed using established remediation techniques such as in-situ chemical oxidation (ISCO), in-situ chemical reduction (ISCR; most notably using zero-valent iron [ZVI]), enhanced in-situ bioremediation (EISB), phytoremediation, soil-washing, pump-and-treat, soil vapour extraction (SVE), thermal treatment, and excavation and disposal. Decades of field applications have shown that these techniques can successfully treat or control contaminants in higher permeability subsurface materials such as sands, but achieve only limited success at sites where low permeability soils, such as silts and clays, prevail. Electrokinetics (EK), a soil remediation technique mostly recognized in in-situ treatment of low permeability soils, has, for the last decade, been combined with more conventional techniques and can significantly enhance the performance of several of these remediation technologies, including ISCO, ISCR, EISB and phytoremediation. Herein, we discuss the use of emerging EK techniques in tandem with conventional remediation techniques, to achieve improved remediation performance. Furthermore, we highlight new EK applications that may come to play a role in the sustainable treatment of the contaminated subsurface.

Molecular variability of cowpea mild mottle virus infecting soybean in Brazil.

Molecular variability was assessed for 18 isolates of cowpea mild mottle virus (CPMMV, genus Carlavirus, family Betaflexiviridae) found infecting soybean in various Brazilian states (Bahia, Goiás, Maranhão, Mato Grosso, Minas Gerais, Pará) in 2001 and 2010. A variety of symptoms was expressed in soybean cv. CD206, ranging from mild (crinkle/blistering leaves, mosaic and vein clearing) to severe (bud blight, dwarfing, leaf and stem necrosis). Recombination analysis revealed only one CPMMV isolate to be recombinant. Pairwise comparisons and phylogenetic analysis were performed for partial genomes (ORF 2 to the 3' terminus) and for each ORF individually (ORFs 2 to 6), showing the isolates to be distinct. The topology of the phylogenetic tree could be related to symptoms, but not to the year of collection or geographical origin. Additionally, the phylogenetic analysis supported the existence of two distinct strains of the virus, designated CPMMV-BR1 and CPMMV-BR2, with molecular variations between them.

Assessing fly ash treatment: remediation and stabilization of heavy metals.

Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete.

Molecular characterization of cajá, Spondias mombin (Anacardiaceae), by RAPD markers.

The arboreal species Spondias mombin L. (Anacardiaceae) is widely distributed in Brazil, where the fruits, known by the common name of cajá, are an important commercial commodity. We evaluated genetic variability among 32 cajá accessions of the Germplasm Collection of Embrapa Meio-Norte using RAPD technique. Reaction conditions for efficient RAPD amplifications were optimized in preliminary tests, and primers were selected from a set designed by the University of British Columbia on the basis of high levels of polymorphism and adequate band resolution. The 21 primers employed in the final analysis produced 145 fragments, 79% of which were polymorphic. Based on the RAPD data, a dendrogram was constructed using the unweighted pair group method with arithmetic mean clustering technique. The 32 cajá accessions were classified into three main groups with a mean genetic similarity of 68.8%. Group I comprised 26 accessions (74.1% similarity), and group II included five accessions (74.0% similarity), while group III consisted of one accession (BGC 06), which exhibited the lowest similarity coefficients. Accessions BGC 06 and BGC 31 were the most unrelated and, hence, most suitable for initial crossings in order to obtain high levels of segregation. We concluded, based on the repeatability and reproducibility tests, that the RAPD technique is reliable and efficient for revealing the genetic diversity of cajá accessions, which will be useful for genetic improvement programs.

Heavy metal migration during electroremediation of fly ash from different wastes--modelling.

Fly ash is an airborne material which is considered hazardous waste due to its enrichment on heavy metals. Depending on the waste from which they are originated, fly ash may be further valorised, e.g. as soil amendment or concrete and ceramics adjuvant, or landfilled, when defined as hazardous material. In any case, heavy metal content has to be decreased either for fly ash valorisation or for complying with landfill criteria. The electrodialytic (EDR) process is a remediation technique based on the principle of electrokinetics and dialysis, having the aim to remove heavy metals from contaminated solid media. EDR was here applied to fly ashes from the combustion of straw (ST), from the incineration of municipal solid waste (DK and PT) and from the co-combustion of wood (CW). A statistical study, using F tests, Bonferroni multiple comparison method and a categorical regression, was carried out to determine which variables ("Ash type", "Duration", "Initial pH", "Final pH", "Acidification" and "Dissolution") were the most significant for EDR efficiency. After establishing these, the selected variables were then used to characterize some kinetic parameters, from metals migration during EDR, using a biregressional design. Cd, Cr, Cu, Ca and Zn migration velocity and acceleration to the electrodes (anode and cathode) were then considered. Cd and Cu migration to the cathode were found to be significantly influenced by "Ash type", "Duration", "Final pH" and "Dissolution".

Electroremediation of straw and co-combustion ash under acidic conditions.

Biomass, such as wood and straw, is currently used in EU as a renewable energy source for energy production and this application is expected to rise in coming years. Combined heat and power installations produce fly ash, which is considered hazardous waste. The fly ash management issue should be addressed before biomass combustion is considered a truly sustainable technology. The electrodialytic process is a remediation technique able to assist the management of fly ash. For this work, straw and co-combustion of wood ash are briefly characterized and their electrodialytic treatment is carried out under acidic conditions. Straw ashes presented high removal rates for Ca, Cu, Cr and particularly for Cd, which has been reduced to a level bellow the established by Danish regulations. Acidification also induced a high dissolution and a lower pH of the ash. Fly ash from co-combustion of wood presents similarities with wood ash alone. However, further characterization should be carried out before any comparison regarding applicable legislation. Under acidic conditions, the electrodialytic treatment was not effective for the co-combustion wood ash. The heavy metals appeared in the least soluble fraction of this ash and lowering the pH of such an alkaline material does not mean sustainability and may hinder its reuse.

Hepatitis C virus genotypes in hemophiliacs in the state of Minas Gerais, Brazil.

BACKGROUND: Hepatitis C virus (HCV) is a positive-strand RNA virus composed of at least 10 genotypes and dozens of subtypes. Six major genotypes can be distinguished by restriction fragment length polymorphism (RFLP) analysis of the amplified 5' noncoding region (NCR) of the genome. The genotypes are unequally distributed throughout the world. Types 1 and 3 are most common in Europe and the United States. Although fewer studies have been performed in Brazil, the pattern seems to mirror that in the other areas. HCV infection is highly prevalent among hemophiliacs and is a major cause of chronic liver disease. STUDY DESIGN AND METHODS: This study investigated a sample of the hemophiliac population in the state of Minas Gerais, Brazil, by RFLP analysis of the 5' NCR. RESULTS: It was observed that 84.1 percent were of genotype 1 and 13.6 percent of genotype 3. Sequence analysis of nine isolates confirmed the RFLP results and determined that all of the type 1 isolates belonged to subtype 1a. Phylogenetic analysis by parsimony and distance revealed that lineages of genotypes 1, 2, and 3, and 4 could be separated. The isolates of type 3 from this study were distinct from published sequences, which possibly indicated their different geographical origin. CONCLUSION: Although the frequency of genotypes observed (types 1 and 3) among hemophiliacs in the state of Minas Gerais was higher than that in the southern part of the country, these frequencies were not different from those in other groups of patients in Brazil and other countries studied. Further investigation is needed of the evidence that the type 3 isolates observed in these studies are significantly different from other isolates previously characterized by sequence analysis.

Censo leprológico intensivo: Usina Ester, Município de Cosmópolis, Estado de São Paulo. Dispensário de Lepra de Campinas, 1959-1960

De agosto de 1959 a janeiro de 1960 procedeu-se na Usina Ester, Município de Cosmópolis um censo leprológico intensivo, mediante o exame dermatológico da sua população. A medida pode ser viável em 100% dada a existência de um cadastro nominal de todas as pessoas que la residiam. O trabalho constiu de tres fases: 1) Exame dermatológico e reação de Mitsuda nos escolares. 2) Convocação das demais pessoas para exame em locais previamente escolhidos. 3) Busca de faltosos (100 indivíduos), com a colaboração de uma doutora. Feito o confronto das várias colônias da Fazenda, apurou-se que 100% dos seus habitantes haviam se submetido aos exames sem o encontro de um único caso novo de M.H. Inúmeras outras dermatoses fotram registradas. Na população escolar praticou-se também a reação de Mitsuda, observando-se englobadamente 75% de positividade (+, ++ e +++); entre escolares comunicantes essa positividade apenas atingiu 30%. Em três, das 8 (oito) classes escolares, foram administradas aos alunos 6 doses de BCG fresco, entre a aplicação e a leitura da R. M. Não se verificou diferença significante nos resultados da lepromina entre essas classes e as demais que não usuaram o BCG...