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This study aimed to assess antioxidant effects of melatonintreatment compared to N-acetylcysteine (NAC) and to their combination in asickle cell suspension. Sickle erythrocytes were suspended in phosphate-buffered saline, pH 7.4, composing external control group. They were alsosuspended and incubated at 37°C either in the absence (experimental controlgroup) or in the presence of NAC, melatonin and their combination atconcentrations of 100 pM, 100 nM and 100 lM for 1 hr (treatment groups).The melatonin influences were evaluated by spectrophotometric [hemolysisdegree, catalase (CAT), glutathione S-transferase (GST), glutathioneperoxidase (GPx), glutathione reductase (GR), glucose-6-phosphatedehydrogenase (G6PDH), and superoxide dismutase (SOD) activities] andchromatographic methods [glutathione (GSH) and malondialdehyde (MDA)levels]. Incubation period was able to cause a rise about 64% on hemolysisdegree as well as practically doubled the lipid peroxidation levels (P < 0.01).However, almost all antioxidants tested treatments neutralized this incubationeffect observed in MDA levels. Among the antioxidant biomarkers evaluated,we observed a modulating effect of combined treatment on GPx and SODactivities (P < 0.01), which showed ~25% decrease in their activities. Inaddition, we found an antioxidant dose-dependent effect for melatonin onlipid peroxidation (r = 0.29; P = 0.03) and for combined antioxidanttreatments also on MDA levels (r = 0.37; P = 0.01) and on SOD activity(r = 0.54; P < 0.01). Hence, these findings contribute with important insightthat melatonin individually or in combination with NAC may be useful forsickle cell anemia management.
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Wurtzite-structured ZnS nanostructures have been synthesized by means of a microwave-solvothermal method at 140°C using three precursors (chloride, nitrate and acetate). Different techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV–vis) absorption spectroscopy and photoluminescence (PL) measurements have been employed to characterize this material. The structure, surface morphology, chemical composition and optical properties were investigated as function of precursor. In order to complement experimental results, first principles calculations at DFT level were carried out in order to obtain the relative stability of the proposed intermediates along the formation mechanism. - See more at: http://www.eurekaselect.com/117237/article#sthash.GzvnCBTB.dpuf
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The city of Vazante-MG is of great socioeconomic and environmental interest because it is the most important zinc producer district of Brazil. The mineral processing and geochemical processes may determine high concentrations of heavy metals in water intended for human consumption. Thus, the present study aimed to quantify and evaluate the heavy metal genotoxicity of artesian water in the city by Atomic absorption spectrophotometer analysis and testing with the Allium cepa test, respectively. This study reveals a chemical contamination in well water in the city, caused by the presence of heavy metals. Therefore, it can be considered that the high levels of heavy metals found in water samples are correlated with the genotoxic events observed in root cells of A. cepa.
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Introduction: Alkalinization potential is a fundamental property of endodontic epoxy-based cements containing calcium hydroxide. Studies have shown discrepant pH results for same materials at different evaluation periods. A possible reason accounting for these differences may be the assessment procedures. Objective: To evaluate the pH value of an epoxy-based cement (Sealer 26) in different periods of analysis, using two assessment methods. Material and methods: Sealer 26 was manipulated and immediately placed into polyethylene tubes (n=10, each group) and immersed in distilled water. In G1, the tubes were kept in the same water during all experiment; and in G2, the tubes were removed and placed into another flask with an equal amount of water after the pH evaluation. The pH of these solutions was measured at 24 hours, 7, 14 and 28 days. Analysis were made within the same group according to the experimental periods and between groups in each experimental period. Data were submitted to ANOVA (α = 5%) and t test, respectively. Results: For G1 and G2, all periods showed different pH values (p < 0.05), except between 14 and 28 days (p > 0.05) and between 7 and 14 days (p > 0.05), respectively. In each period, no significant differences were observed between the groups. Conclusion: The method to obtain the pH values in different experimental periods no interfered in the final results. However, difference was observed when the results were analyzed at same group.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Spindle cell lipoma is a benign lipomatous neoplasm, which rarely occurs in the oral cavity. The aims of this paper are to report a case of spindle cell lipoma located in buccal mucosa and discuss the main clinical, histological, and immunohistochemical findings of this entity. Thus, we report a 4-year history of an asymptomatic smooth surface nodule in an elderly Caucasian man with clinical hypothesis of fibroma. The histopathological examination showed spindle cells, mature adipose tissue, and many mast cells in a stroma of connective tissue presenting ropey collagen fibers bundles. After immunohistochemical analysis, the final diagnosis was spindle cell lipoma.
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Oil refinery effluents contain many chemicals at variable concentrations. Therefore, it is difficult to predict potential effects on the environment. The Atibaia River (SP, Brazil), which serves as a source of water supply for many municipalities, receives the effluents of one of the biggest oil refinery of this country. The aim of this study was to identify the (eco)toxicity of fresh water sediments under the influence of this oil refinery through neutral red (cytotoxicity) and ethoxyresorufin-O-deethylase (EROD) assays (AhR-mediated toxicity) in RTL-W1 cells (derived from fish liver). Once the refinery captures the waters of Jaguarí River for the development of its activities and discharges its effluents after treatment into the Atibaia River, which then flows into Piracicaba River, sediments from both river systems were also investigated. The samples showed a high cytotoxic potential, even when compared to well-known pollution sites. However, the cytotoxicity of samples collected downstream the effluent was not higher than that of sediments collected upstream, which suggested that the refinery discharges are not the main source of pollution in those areas. No EROD activity could be recorded, which could be confirmed by chemical analyses of polycyclic aromatic hydrocarbons (PAHs) that revealed a high concentration of phenanthrene, anthracene, fluoranthene, and pyrene, which are not EROD inducers in RTL-W1 cells. In contrast, high concentrations of PAHs were found upstream the refinery effluent, corroborating cytotoxicity results from the neutral red assay. A decrease of PAHs was recorded from upstream to downstream the refinery effluent, probably due to dilution of compounds following water discharges. On the other hand, these discharges apparently contribute specifically to the amount of anthracene in the river, since an increase of anthracene concentrations could be recorded downstream the effluent. Since the extrapolation of results from acute toxicity to specific toxic effects with different modes of action is a complex task, complementary bioassays covering additional specific effects should be applied in future studies for better understanding of the overall ecotoxicity of those environments.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conscious sedation has become established as an important alternative to general anesthesia (GA) in dental treatment of patients with intellectual disability (ID). Aim: to investigate dental patients undergoing sedation using a mean dose of 0.6 mg/kg intravenous midazolam and the adverse events of sedation in patients with ID. Methods: This study analyzed the records of 163 dental patients with ID aged between 2 and 76 years who had undergone conscious intravenous sedation (CIV) using a mean dose of 0.61 mg/kg of midazolam at Araçatuba Dental School, São Paulo State University, Brazil. The efficacy and complications induced by CIV were evaluated in each subject. Results: CIV was effective for dental treatment in 80% of the cases. A total of 626 dental procedures were performed. The mean treatment time was 33.9 minutes. There was statistically significant difference (p<0.05) between absence and presence of adverse reactions. Adverse reactions were observed in 21.47% of the cases. Conclusions: The results of this study showed that CIV is a useful method for dental treatment of patients with ID and these patients can need higher doses of sedative to reach an adequate level of sedation.
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Human monkeypox has never been reported in Ghana, but rodents captured in forested areas of southern Ghana were the source of the monkeypox virus introduced into the United States in 2003. Subsequent to the outbreak in the United States, 204 animals were collected from two commercial trapping sites in Ghana. Animal tissues were examined for the presence of orthopoxvirus (OPXV) DNA using a real-time polymerase chain reaction, and sera were assayed for antibodies against OPXV. Animals from five genera (Cricetomys , Graphiurus , Funiscirus, and Heliosciurus ) had antibodies against OPXV, and three genera (Cricetomys , Graphiurus , and Xerus) had evidence of OPXV DNA in tissues. Additionally, 172 persons living near the trapping sites were interviewed regarding risk factors for OPXV exposure, and their sera were analyzed. Fifty-three percent had IgG against OPXV; none had IgM. Our findings suggest that several species of forest-dwelling rodents from Ghana are susceptible to naturally occurring OPXV infection, and that persons living near forests may have low-level or indirect exposure to OPXV-infected animals, possibly resulting in sub-clinical infections.
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A taxonomic and annotated functional description of microbial life was deduced from 53 Mb of metagenomic sequence retrieved from a planktonic fraction of the Neotropical high Andean (3,973 meters above sea level) acidic hot spring El Coquito (EC). A classification of unassembled metagenomic reads using different databases showed a high proportion of Gammaproteobacteria and Alphaproteobacteria (in total read affiliation), and through taxonomic affiliation of 16S rRNA gene fragments we observed the presence of Proteobacteria, micro-algae chloroplast and Firmicutes. Reads mapped against the genomes Acidiphilium cryptum JF-5, Legionella pneumophila str. Corby and Acidithiobacillus caldus revealed the presence of transposase-like sequences, potentially involved in horizontal gene transfer. Functional annotation and hierarchical comparison with different datasets obtained by pyrosequencing in different ecosystems showed that the microbial community also contained extensive DNA repair systems, possibly to cope with ultraviolet radiation at such high altitudes. Analysis of genes involved in the nitrogen cycle indicated the presence of dissimilatory nitrate reduction to N2 (narGHI, nirS, norBCDQ and nosZ), associated with Proteobacteria-like sequences. Genes involved in the sulfur cycle (cysDN, cysNC and aprA) indicated adenylsulfate and sulfite production that were affiliated to several bacterial species. In summary, metagenomic sequence data provided insight regarding the structure and possible functions of this hot spring microbial community, describing some groups potentially involved in the nitrogen and sulfur cycling in this environment. Citation: Jimenez DJ, Andreote FD, Chaves D, Montana JS, Osorio-Forero C, et al. (2012) Structural and Functional Insights from the Metagenome of an Acidic Hot Spring Microbial Planktonic Community in the Colombian Andes. PLoS ONE 7(12): e52069. doi:10.1371/journal.pone.0052069
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CONTEXT AND OBJECTIVE: Injuries are an important cause of morbidity during adolescence, but can be avoided through learning about some of their characteristics. This study aimed to identify the most frequent injuries among adolescents attended at an emergency service. DESIGN AND SETTING: Retrospective descriptive study on adolescents attended at the emergency service of the Teaching Health Center, Faculdade de Medicina de Ribeirao Preto (FMRP), between January 1, 2009, and September 30, 2009. METHODS: Age, sex, type of injury, site, day and time of occurrence, part of body involved, care received, whether the adolescent was accompanied at the time of injury and whether any type of counseling regarding injury prevention had been given were analyzed. RESULTS: Among 180 adolescents attended, 106 (58.8%) were boys and 74 (41.1%) were girls. Their ages were: 10 to 12 (66/36.6%), 12 to 14 (60/33.3%) and 14 to 16 years (54/30%). The injuries had occurred in public places (47.7%) and at home (21.1%). The main types were bruises (45.1%) and falls (39.2%), involving upper limbs (46.1%), lower limbs (31%) and head/neck (13.1%). The injuries occurred in the afternoon (44.4%) and morning (30%), on Mondays (17.7%) and Thursdays (16.6%). Radiological examinations were performed on 53.8%. At the time of injury, 76.1% of the adolescents were accompanied. Some type of counseling about injury prevention had been received by 39.4%. CONCLUSIONS: Although the injuries were of low severity, preventive attitudes need to be incorporated in order to reduce the risks and provide greater safety for adolescents.
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During the evolutionary process of the sex chromosomes, a general principle that arises is that cessation or a partial restriction of recombination between the sex chromosome pair is necessary. Data from phylogenetically distinct organisms reveal that this phenomenon is frequently associated with the accumulation of heterochromatin in the sex chromosomes. Fish species emerge as excellent models to study this phenomenon because they have much younger sex chromosomes compared to higher vertebrates and many other organisms making it possible to follow their steps of differentiation. In several Neotropical fish species, the heterochromatinization, accompanied by amplification of tandem repeats, represents an important step in the morphological differentiation of simple sex chromosome systems, especially in the ZZ/ZW sex systems. In contrast, multiple sex chromosome systems have no additional increase of heterochromatin in the chromosomes. Thus, the initial stage of differentiation of the multiple sex chromosome systems seems to be associated with proper chromosomal rearrangements, whereas the simple sex chromosome systems have an accumulation of heterochromatin. In this review, attention has been drawn to this contrasting role of heterochromatin in the differentiation of simple and multiple sex chromosomes of Neotropical fishes, highlighting their surprising evolutionary dynamism.