We discuss how different accelerator-based techniques can be employed synergistically as a powerful analytical tool for forensic studies of foodstuff. Brazilian and Jamaican coffees were chosen as a ...showcase due to its popularity and potential risk of adulteration and/or falsification. Comprehensive characterization of major and trace elements, age since production and compound contents were achieved using different techniques, including PIXE (Particle-Induced X-ray Emission), FTIR (Fourier Transform Infrared), and AMS-14C (Accelerator Mass Spectrometry – Radiocarbon Analysis). While PIXE provides information on the elements present in the samples, FTIR probes the types of compounds through their vibrational spectra. Finally, AMS-14C is capable of dating organic samples regarding their harvesting time. Five different laboratories from research institutions around the world took part in the experiments. The integration of the results obtained with different techniques provided multifaceted perspectives on the coffee under study, thus allowing a direct assessment of the material for forensic purposes such as authentication, determination of provenance, and combat counterfeiting.
•Accelerator-based techniques helping forensic studies of coffee.•PIXE: provides information on the elemental profile of coffee.•AMS-14C: provides information on the date of production.•ATR-FTIR: provides information on the molecular profile of coffee.•Overall results show a synergetic integration of these techniques.
SCOPE: Postmenopausal women are often affected by a group of metabolic disorders related to oxidative stress. Alternative treatments that can improve the quality of life of these women have been the ...subject of recent studies. The objective of this study was to evaluate the response to oxidative stress in the brains of rats following ovariectomy, and to determine enzymatic and nonenzymatic antioxidant responses when the animals received 3 months of dietary supplementation. METHODS AND RESULTS: Ovariectomy produced changes in antioxidant profiles characterized by reductions in glutathione S‐transferase activity, H₂O₂ consumption, superoxide dismutase activity, and vitamin C levels and increases in protein carbonylation. Docosahexaenoic fatty acid (DHA) supplementation restored these parameters to normal values and increased values of other antioxidants (glutathione peroxidase and total glutathione). However, DHA supplementation also increased protein carbonylation and lipid peroxidation. Eicosapentaenoic acid supplementation produced no changes in antioxidants, but decreased lipid peroxidation. Lipoic acid supplementation increased consumption of H₂O₂ and decreased protein carbonylation and lipid peroxidation. CONCLUSION: These results suggest that the antioxidant response to omega‐3 varies in different tissues, and in this study DHA treatment had a prooxidant effect in the brain. Lipoic acid treatment, on the other hand, had a protective effect, reducing markers of oxidative damage.
► Tobacco farming presents hazards to those who cultivate and harvest the plant. ► The genotoxic and mutagenic effects in tobacco farmers were investigated. ► Genetic susceptibility, oxidative stress ...and trace elements were determined. ► Results show that farmers are exposed to substances with genotoxic potential. ► This investigation suggests that tobacco farmers are suffering occupational risk.
Tobacco farming presents several hazards to those who cultivate and harvest the plant. The genotoxic and mutagenic effects in tobacco farmers were investigated. In order to verify the relationship between genetic susceptibility and biomarkers GSTT1, GSTM1, GSTP1, CYP2A6, PON, OGG1, RAD51, XRCC1, and XRCC4 genes polymorphism were evaluated. Oxidative stress markers and trace elements content were determined. Peripheral blood cells samples were collected from 111 agricultural workers during pesticides application and leaf harvest, and 56 non-exposed subjects. Results show that farmers are exposed to mixture of substances with genotoxic and cytotoxic potential. Only GSTM1 null and CYP2A6*9 showed significant associations with cytokinesis-blocked micronuclei assay results. In pesticide application an increase in trace elements content was observed. The results indicated that exposure to pesticides and nicotine can influence antioxidant enzymes activity. Our study drives the attention once more to the need for occupational training on safe work environment for farm workers.
Chitosan based membranes to be applied on wound healing as topical drug delivery systems were developed by graft copolymerization of acrylic acid (AA) and 2-hydroxyethyl methacrylate (HEMA) onto ...chitosan using cerium ammonium nitrate as chemical initiator. Evidence for graft copolymerization of the vinyl monomers onto chitosan was obtained by FTIR and DMTA. Swelling degree, cytotoxicity, thrombogenicity and haemolytic activity of these membranes were evaluated. Chitosan-graft-AA-graft-HEMA showed to be the best matrix for drug delivery systems than chitosan-graft-AA because it retains good swelling properties, but the content in HEMA has improved cytocompatibility, hemocompatibility and thrombogenic character.
Abstract Few antifungals available today are effective in treating biofilms. Thus, it is urgent to discover new compounds, such as natural products, that provide improvements to existing treatments ...or the development of new antifungal therapies. This study aimed to perform a comparative analysis between the green propolis extract (PE) and its by-product, a waste of propolis extract (WPE) through a screening with Candida sp., Fusarium sp. and Trichophyton sp. The antifungal property of PE and WPE was assessed by the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) determination in planktonic cells. The influence of both extracts on the inhibition of biofilm formation in these fungi was also tested. The WPE MIC and MFC values (68.75 to 275.0 µg/mL) were three to twelve times lower than the values obtained for PE (214.06 to 1712.5 µg/mL). PE was more efficient than WPE in inhibiting the biofilm initial phase, especially in C. albicans. Meanwhile, WPE had dose-dependent behavior for the three fungi, being more effective on filamentous ones. Both PE and WPE showed excellent antifungal activity on planktonic cells and demonstrated great efficacy for inhibiting biofilm formation in the three fungi evaluated.
In the present study, we demonstrated the in vitro activity of endophytic phosphate-solubilizing bacteria (PSB). Fifty-five endophytic PSB that were isolated from sap, leaves, and roots of maize were ...tested for their ability to solubilize tricalcium phosphate and produce organic acid. Partial sequencing of the 16S rRNA-encoding gene showed that the isolates were from the genus Bacillus and different species of Enterobacteriaceae. The phosphate solubilization index on solid medium and phosphate solubilization in liquid medium varied significantly among the isolates. There was a statistically significant difference (P ≤ 0.05) for both, the values of phosphate-solubilizing activity and pH of the growth medium, among the isolates. Pearson correlation was statistically significant (P ≤ 0.05) between P-solubilization and pH (R = -0.38), and between the gluconic acid production and the lowering of the pH of the liquid medium at 6 (R = 0.28) and 9 days (R = 0.39). Gluconic acid production was prevalent in all the PSB studied, and Bacillus species were most efficient in solubilizing phosphate. This is the first report on the characterization of bacterial endophytes from maize and their use as potential biofertilizers. In addition, this may provide an alternative strategy for improving the phosphorus acquisition efficiency of crop plants in tropical soils.
We demonstrated recently that P8A-CCL2, a monomeric variant of the chemokine CCL2/MCP-1, is unable to induce cellular recruitment in vivo, despite full activity in vitro. Here, we show that this ...variant is able to inhibit CCL2 and thioglycollate-mediated recruitment of leukocytes into the peritoneal cavity and recruitment of cells into lungs of OVA-sensitized mice. This anti-inflammatory activity translated into a reduction of clinical score in the more complex inflammatory model of murine experimental autoimmune encephalomyelitis. Several hypotheses for the mechanism of action of P8A-CCL2 were tested. Plasma exposure following s.c. injection is similar for P8A-CCL2 and wild-type (WT) CCL2, ruling out the hypothesis that P8A-CCL2 disrupts the chemokine gradient through systemic exposure. P8A-CCL2 and WT induce CCR2 internalization in vitro and in vivo; CCR2 then recycles to the cell surface, but the cells remain refractory to chemotaxis in vitro for several hours. Although the response to P8A-CCL2 is similar to WT, this finding is novel and suggests that despite the presence of the receptor on the cell surface, coupling to the signaling machinery is retarded. In contrast to CCL2, P8A-CCL2 does not oligomerize on glycosaminoglycans (GAGs). However, it retains the ability to bind GAGs and displaces endogenous JE (murine MCP-1) from endothelial surfaces. Intravital microscopy studies indicate that P8A-CCL2 prevents leukocyte adhesion, while CCL2 has no effect, and this phenomenon may be related to the mechanism. These results suggest that oligomerization-deficient chemokines can exhibit anti-inflammatory properties in vivo and may represent new therapeutic modalities.
In recent years, propolis extract (PE) has demonstrated antimicrobial and anti-inflammatory properties. The aim of this study was to evaluate the antifungal activity of a bioadhesive thermoresponsive ...system containing 16% propolis (BTSP 16%) against Microsporum canis, Nannizzia gypsea, Trichophyton mentagrophytes and T. rubrum. We also evaluated PE alone against the same strains. The results showed that both PE and BTSP 16% significantly reduced the fungal viability of all evaluated strains. In addition, they interacted with the biofilm of these species in different stages of biofilm formation. We observed that the bioadhesive and thermoresponsive properties of BTSP 16% prolonged propolis presence at infection sites, leading to positive results against planktonic fungal cells and mature biofilms. These characteristics make this formulation a valuable alternative treatment for dermatomycosis.
Monolithic tin oxide aerogels synthesized using the epoxide technique were characterized with X-ray diffraction, diffusive reflectance spectroscopy, infrared spectroscopy, particle induced X-ray ...emission and photoluminescence. Our results indicate that the resulting aerogel is an electrical semi-insulator. This happens due to an incomplete chemical reaction that leaves chloride and hydroxide ions unreacted. These ions form complexes with oxygen vacancy sites producing electron trapping. Furthermore, ions of Cu, Zn and Fe were identified as naturally occurring impurities in the gel matrix, substituting Sn+4 ions.
•High surface area tin oxide aerogel was grown using the epoxide technique.•We study the electronic structure of the material using spectroscopy and photoluminescence.•The absence of electrical conductivity is a consequence of high electron trapping.•Ions of Cu, Fe and Zn were identified by PIXE as naturally occurring impurities.
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