Investigation of pesticide exposure by genotoxicological, biochemical, genetic polymorphic and in silico analysis.

Soybean farmers are exposed to various types of pesticides that contain in their formulations a combination of chemicals with genotoxic and mutagenic potential. Therefore, the objective of this paper was to evaluate the genetic damages caused by this pesticide exposure to soybean producers in the state of Mato Grosso (Brazil), regarding biochemical, genetic polymorphic and in silico analyses. A total of 148 individuals were evaluated, 76 of which were occupationally exposed and 72 were not exposed at all. The buccal micronucleus cytome assay (BMCyt) detected in the exposed group an increase on DNA damage and cell death. No inhibition of butyrylcholinesterase (BchE) was observed within the exposed group. The detection of inorganic elements was made through the particle-induced X-ray emission technique (PIXE), which revealed higher concentrations of Bromine (Br), Rubidium (Rb) and Lead (Pb) in rural workers. A molecular model using in silico analysis suggests how metal ions can cause both DNA damage and apoptosis in the exposed cells. Analysis of the compared effect of X-ray Repair Cross-complement Protein 1 (XRCC1) and Paraoxonase 1 (PON1) genotypes in the groups demonstrated an increase of binucleated cells (exposed group) and nuclear bud (non-exposed group) in individuals with the XRCC1 Trip/- and PON1 Arg/- genes. There was no significant difference in the telomere (TL) mean value in the exposed group in contrast to the non-exposed group. Our results showed that soybean producers showed genotoxic effect and cell death, which may have been induced by exposure to complex mixtures of agrochemicals and fertilizers. In addition, XRCC1 Arg/Arg could, in some respects, provide protection to individuals.

The influence of the winemaking process on the elemental composition of the Marselan red wine.

BACKGROUND: The elemental profile of the Marselan wine cycle was studied with a single ion-beam technique, namely particle-induced X-ray emission (PIXE). Samples were collected from all of the major stages involved in the wine cycle, including soil, vine plant, grape, and different stages of wine processing. RESULTS: The results show the influence of field practices on the elemental composition of leaves, branches, grapes, and soil. Mechanisms of element precipitation and elimination from the wine were identified through the changes in the elemental concentrations measured during the post-harvesting processes. The concentrations of some elements, such as Al, Si, K, and Ni, did not vary for grapes collected at different maturation stages. On the other hand, changes in the concentrations of Si, Cl, Ca, Cu, and K were observed right after the maceration and pressing processes in young wine. Finally, the reduction in the Cu concentration during the last stages of the wine cycle is related to its precipitation in the storage tanks. CONCLUSIONS: It was found that field practices and winemaking processes played distinct roles in the elemental composition of grapes and wine from different preparation stages. Moreover, PIXE proved to be a suitable analytical tool for the analysis of the whole wine cycle because it handles solid and liquid samples in a clean and straightforward manner. © 2019 Society of Chemical Industry.

From alumina nanopores to nanotubes: dependence on the geometry of anodization system.

The Conventional anodization of commercial aluminum sheets with a phosphoric acid electrolyte was employed for the preparation of alumina nanopore and/or nanotube structures. Modifying the system geometry (the ratio of platinum to aluminum electrode areas) controlled the nature of the anodization process (mild to hard). Nanotube formation was observed after low temperature preferential chemical etching of the defective corners of the hexagonal alumina cells using the same solution from the anodization process. Electrode geometry can be used to combine mild and hard anodization with low temperature etching to tune the alumina morphology from 100% nanopores to 100% nanotubos coverage.

Elemental analysis of Brazilian coffee with ion beam techniques: From ground coffee to the final beverage.

Brazilian coffee is well known worldwide due to its quality and richness in taste. The aim of the present study is to provide the elemental characterization of Brazilian coffee along different stages of the drip brewing process. To that end, samples from roasted ground coffee, spent coffee, paper filters and the final beverage were analyzed with one single ion beam technique, namely particle-induced X-ray emission (PIXE). In total, over 140 samples from 8 different Brazilian brands of ground coffee were analyzed. Large differences in some elemental concentrations were observed among different brands and among different batches of a single brand, which leads to high variances in the data. Concerning the beverage preparation, the analysis of the spent coffee shows that the transfer ratio from the ground coffee to the beverage differs for each element. Our results indicate that potassium and chlorine have the highest transfer ratio. Moreover, the concentration of rubidium is relatively high in drinking coffee. Finally, there is no influence of the elemental composition of paper filter in the preparation of drinking coffee.

Changes in the element concentration of the dorsal hippocampus CA1 region during memory consolidation and reconsolidation.

The concentration and distribution of Mg, P, Cl, K, Cu and Zn in the dorsal hippocampus CA1 region of rat brains were studied during memory consolidation and reconsolidation processes stimulated with inhibitory avoidance (IA) tests. Experimental rats were divided into four groups: i) group not submitted to inhibitory avoidance task (IA-N); ii) group submitted to inhibitory avoidance training session (IA-Y); iii) group submitted to inhibitory avoidance reactivation session but did not step down from the platform (IAR-N); and iv) group submitted to avoidance reactivation session and stepped down from the platform (IAR-Y). Elemental concentration and distribution in the CA1 hippocampus region were obtained through the Particle-Induced X-ray Emission (PIXE) technique. The results indicate that the concentration of Mg, P, Cl, K and Cu increased during memory consolidation. During the memory reconsolidation process, the concentrations of Mg, P, Cl and K increased, while Cu and Zn had no significant changes with respect to their basal condition. These results show that the major part of these elements may be engaged in memory consolidation could be also participating in memory reconsolidation. For all elements, the general trend related to their concentration did not change during reconsolidation regardless the presence of a novelty event, i.e. stepping down from the platform.

Blood Trace Element Concentrations in Polycystic Ovary Syndrome: Systematic Review and Meta-analysis.

Polycystic ovary syndrome (PCOS) is a prevalent condition in women of reproductive age. PCOS is characterized by androgen excess and chronic anovulation and associated with low-grade inflammation and metabolic comorbidities. Some trace elements have been linked to pathophysiological mechanisms of oxidative stress and inflammation in different disorders. Therefore, we conducted a systematic review and meta-analysis of the available evidence regarding trace element concentrations in PCOS. We reviewed MEDLINE and EMBASE in search of case-control, cross-sectional, and cohort studies published until September 2015. Of 183 studies identified, six were selected for systematic review. All used the Rotterdam criteria for the diagnosis of PCOS. Two studies evaluating chromium and one assessing cobalt levels did not observe differences between PCOS and controls. Another study recorded similar nickel and vanadium levels between the groups, but lower selenium concentrations in women with PCOS compared to controls. Four studies were included in the random effects model meta-analysis, for a total of 264 PCOS and 151 control women. Copper levels were found to be higher in women with PCOS than in controls [mean difference 0.12 ppm (95 % CI 0.07; 0.17 ppm); I 2 = 0 %]. Manganese [mean difference 0.04 ppm (95 % CI -0.05; 0.13 ppm); I 2 = 94.4 %] and zinc concentrations [mean difference 0.02 ppm (95 % CI -0.12; 0.16 ppm); I 2 = 92.4 %] were similar between the groups. The present results suggest a relationship between increased copper concentration and PCOS. This systematic review and meta-analysis is registered in PROSPERO under number CRD42016034036.

Polymerization of carbon nanotubes through self-irradiation.

We have investigated the formation of cross-links between neighboring carbon nanotubes within a bundle. Classical molecular dynamics was used to follow the evolution of the system when it is bombarded by low-energy carbon atoms. We show that it is possible to polymerize carbon nanotubes through irradiation and discuss the most common types of defects produced. Cross-links are created mainly in the direction perpendicular to the surface, and for higher energies, defects are created deeper in the rope. The final defects geometries may provide a realistic input to electronic density first principle calculations.

Brazilian Science between National and Foreign Journals: Methodology for Analyzing the Production and Impact in Emerging Scientific Communities.

In recent decades, we have observed an intensification of science, technology and innovation activities in Brazil. The increase in production of scientific papers indexed in international databases, however, has not been accompanied by an equivalent increase in the impact of publications. This paper presents a methodology for analyzing production and the impact of certain research areas in Brazil related to two aspects: the origin of the journals (national or foreign) and international collaboration. These two variables were selected for being of particular importance in understanding the context of scientific production and communication in countries with emerging economies. The sample consisted of papers written by Brazilian researchers in 19 subfields of knowledge published from 2002 to 2011, totaling 85,082 papers. To calculate the impact, we adopted a normalized indicator called the relative subfield citedness (Rw) using a window of 5 years to obtain measurements evaluated in 2 different years: 2007 and 2012. The data on papers and citations were collected from the Web of Science database. From the results, we note that most of the subfields have presented, from one quinquennium to another, improved performance in the world production rankings. Regarding publication in national and foreign journals, we observed a trend in the distribution maintenance of production of the subfields based on the origin of the journal. Specifically, for impact, we identified a lower Rw pattern for Brazilian papers when they were published in national journals in all subfields. When Brazilian products are published in foreign journals, we observed a higher impact for those papers, even surpassing the average global impact in some subfields. For international collaboration, we analyzed the percentage of participation of foreign researchers and the connection between collaboration and the impact of papers, especially emphasizing the distinction of hyperauthorship papers in terms of production and impact.

Channeling on carbon nanotubes: a molecular dynamics approach.

We have performed classical molecular dynamics on different kinds of carbon nanotubes in order to examine their response to self-irradiation nearly parallel to the tube axis. We have found that the critical angle for channeling decays as a power law. Following the energy loss along the projectile path, we have determined the maximum range as a function of energy at the critical angle. Narrower tubes seem to be more adequate for transporting particles to longer distances.

Effects of Supplemental Acerola Juice on the Mineral Concentrations in Liver and Kidney Tissue Samples of Mice Fed with Cafeteria Diet.

We evaluated the impact of a supplemental acerola juice (unripe, ripe, and industrial) and its main pharmaceutically active components on the concentrations of minerals in the liver and kidney of mice fed with cafeteria diet. Swiss male mice were fed with a cafeteria (CAF) diet for 13 weeks. The CAF consisted of a variety of supermarket products with high energy content. Subsequently, animals received one of the following food supplements for 1 month: water, unripe acerola juice, ripe acerola juice, industrial acerola juice, vitamin C, or rutin. Mineral concentrations of the tissues were determined by particle-induced X-ray emission (PIXE). Our study suggests that the simultaneous intake of acerola juices, vitamin C, or rutin in association with a hypercaloric and hyperlipidic diet provides change in the mineral composition of organisms in the conditions of this study, which plays an important role in the antioxidant defenses of the body. This may help to reduce the metabolism of the fat tissue or even to reduce the oxidative stress.

Micro and nano-texturization of intermetallic oxide alloys by a single anodization step: preparation of artificial self-cleaning surfaces.

Micro- and nanostructures of Ti-γCu (γ = 0, 30, 50, 70, and 100 wt %) intermetallic alloys were produced through a single anodization step. It was found that the original alloy composition influences the final oxide morphology obtained after anodization which presented formation of a microstructure with nanotubes, nanoparticles or nanopillars on the surface. Pure Ti and Cu oxide metals and their alloys presented hydrophilic or superhydrophilic properties immediately after anodization. When the anodized pure metal and/or Ti-γCu surfaces were functionalized with trimethoxypropylsilane (TPMSi), by dipping and coating with a thin perfluorinated layer, the treated substrates became in all cases superhydrophobic (water contact angles in the range of 152-166°), showing excellent self-cleaning properties with hysteresis below 3°. These results can be explained by a combination of nanomicro morphologies with low surface energy compounds in the topmost monolayers. The decrease in hysteresis was associated with a higher M-OH bond concentration on the anodized surfaces, which allowed for more complete TMPSi coating coverage. This study also indicates that easy and effective fabrication of superhydrophobic surfaces in pure metals and alloys is possible without involving traditional multistep processes.