Search

The intensive use of glyphosate around the world in the last few decades demands constant monitoring of this compound and its metabolite in aquatic compartments. This work aimed to develop a sensitive method for the analysis of glyphosate, AMPA and glufosinate in water by liquid chromatography/tandem mass spectrometry (LC-MS/MS). The method involves analyte concentration by lyophilization (20×) and direct injection on the LC-MS/MS, and was satisfactorily validated at a LOQ of 0.0025 μg L -1 . A total of 142 samples of surface and groundwater collected during the 2021/2022 dry and rainy seasons in the Rio Preto Hydrographic Basin were analyzed. All the 52 groundwater samples were positive for glyphosate (up to 1.5868 μg L -1 , dry season) and AMPA (up to 0.2751 μg L -1 , dry season). A total of 27 of the 90 surface water samples were positive for glyphosate (up to 0.0236 μg L -1 ), and 31 samples for AMPA (up to 0.0086 μg L -1 ), of which over 70 % collected during the dry season. Glufosinate was detected in only five samples, four in groundwater (up to 0.0256 μg L -1 ). The levels found in the samples are much lower than the maximum levels established by the Brazilian legislation for glyphosate and/or AMPA and lower than the most critical toxicological endpoints for aquatic organisms. However, constant monitoring is necessary, demanding sensitive methods to allow the detection of the very low levels of these pesticides in water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Advances in wound treatment depend on the availability of animal models that reflect key aspects of human wound healing physiology. To this date, the accepted mouse models do not reflect defects in the healing process for chronic wounds that are associated with type two diabetic skin ulcers. The long term, systemic physiologic stress that occurs in middle aged or older Type 2 diabetes patients is difficult to simulate in preclinical animal model. We have strived to incorporate the essential elements of this stress in a manageable mouse model: long term metabolic stress from obesity to include the effects of middle age and thereafter onset of diabetes. At six-weeks age, male C57BL/6 mice were separated into groups fed a chow and High-Fat Diet for 0.5, 3, and 6 months. Treatment groups included long term, obesity stressed mice with induction of diabetes by streptozotocin at 5 months, and further physiologic evaluation at 8 months old. We show that this model results in a severe metabolic phenotype with insulin resistance and glucose intolerance associated with obesity and, more importantly, skin changes. The phenotype of this older age mouse model included a transcriptional signature of gene expression in skin that overlapped that observed with elderly patients who develop diabetic foot ulcers. We believe this unique old age phenotype contrasts with current mice models with induced diabetes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Poblete Jara et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The objective of this study was to evaluate if the maximum values (MVs) for pesticides in surface freshwater included in CONAMA directive 357/2005 are safe for aquatic biota, comparing them with ecotoxicology data published in the literature. The terms "aquatic toxicity", "chronic" "acute", "LC 50 ", "EC 50 ", "NOEL", "NOEC" and the name of each pesticide were used for searches on the research platforms. Data from 534 tests reported in 37 published articles and three ecotoxicological databases were included in this study; 24% of the tests were carried out with producer organisms, 34% with primary consumers and 42% with secondary consumers. Microcrustaceans of the Daphnia genus and the fishes Pimephales promelas and Oncorhynchus mykiss were the organisms most used. Atrazine, alachlor and metolachlor were the most investigated pesticides. Atrazine and alachlor are approved in Brazil, with atrazine ranking fourth among the most used pesticides in the country. The results indicated that of the 27 pesticides included in the standard directive, 17 have a risk quotient (RQ) higher than the level of concern for at least one ecotoxicological parameter and may not protect the aquatic biota. The insecticide malathion, used in various agricultural crops in Brazil, was the one that presented the highest RQs (3125 and 3,125,000 for freshwaters classified as 1/2 and 3, respectively), related to a LC 50 (96 h) of 0.000032 µg/L in Chironomus ramosus . The results indicate that CONAMA directive 357/2005 should be updated in line with the current use of pesticides in the country, and the MVs should be re-evaluated so that they do not represent toxicity for the aquatic biota.

The objective of this study was to critically review studies published up to November 2021 that investigated the presence of pesticides in surface freshwater to answer three questions: (1) in which countries were the studies conducted? (2) which pesticides are most evaluated and detected? and (3) which pesticides have the highest concentrations? Using the Prisma protocol, 146 articles published from 1976 to November 2021 were included in this analysis: 127 studies used grab sampling, 10 used passive sampling, and 9 used both sampling techniques. In the 45-year historical series, the USA, China, and Spain were the countries that conducted the highest number of studies. Atrazine was the most evaluated pesticide (56% of the studies), detected in 43% of the studies using grab sampling, and the most detected in passive sampling studies (68%). The compounds with the highest maximum and mean concentrations in the grab sampling were molinate (211.38 µg/L) and bentazone (53 µg/L), respectively, and in passive sampling, they were oxyfluorfen (16.8 µg/L) and atrazine (4.8 μg/L), respectively. The levels found for atrazine, p,p'-DDD, and heptachlor in Brazil were higher than the regulatory levels for superficial water in the country. The concentrations exceeded the toxicological endpoint for at least 11 pesticides, including atrazine (Daphnia LC 50 and fish NOAEC), cypermethrin (algae EC50, Daphnia and fish LC 50 ; fish NOAEC), and chlorpyrifos (Daphnia and fish LC 50 ; fish NOAEC). These results can be used for planning pesticide monitoring programs in surface freshwater, at regional and global levels, and for establishing or updating water quality regulations., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Under high-fat feeding, the hypothalamus atypically undergoes pro-inflammatory signaling activation. Recent data from transcriptomic analysis of microglia from rodents and humans has allowed the identification of several microglial subpopulations throughout the brain. Numerous studies have clarified the roles of these cells in hypothalamic inflammation, but how each microglial subset plays its functions upon inflammatory stimuli remains unexplored. Fortunately, these data unveiling microglial heterogeneity have triggered the development of novel experimental models for studying the roles and characteristics of each microglial subtype. In this review, we explore microglial heterogeneity in the hypothalamus and their crosstalk with astrocytes under high fat diet-induced inflammation. We present novel currently available ex vivo and in vivo experimental models that can be useful when designing a new research project in this field of study. Last, we examine the transcriptomic data already published to identify how the hypothalamic microglial signature changes upon short-term and prolonged high-fat feeding.

The persistent photoconductivity (PPC) effect is a commonly observed behavior in SnO 2 nanostructures. Here we described and studied this effect through a comparative study, based on measurements of electronic transport using network as well as single devices built from SnO 2 nanowires under different experimental conditions. At room temperature, the PPC effect was observed to be more accentuated in single nanowire devices. It was found that nanowire-nanowire junctions play a fundamental role in the device behavior: the decay time of nanowire network (τ = 52 s) is about three orders of magnitude lower than those of single nanowire (τ = 4.57 × 10 4 s). Additionally, it was confirmed that the PPC effect was directly related to the amount of oxygen present in the environment and it is destroyed with increasing temperature. Furthermore, the PPC effect was interpreted based on the surface effect that depends on the capture/emission of electrons by the surface states.

Industrial fermentation generates products through microbial growth associated with the consumption of substrates. The efficiency of industrial production of high commercial value microbial products such as ethanol from glucose (GLU) is dependent on bacterial contamination. Controlling the sugar conversion into products as well as the sterility of the fermentation process are objectives to be considered here by studying GLU and ultraviolet light (UV) sensors. In this work, we present two different approaches of SnO 2 nanowires grown by the Vapor-Liquid-Solid (VLS) method. In the GLU sensor, we use SnO 2 nanowires as active electrodes, while for the UV sensor, a nanowire film was built for detection. The results showed a wide range of GLU sensing and as well as a significant influence of UV in the electrical signal. The effect of a wide range of GLU concentrations on the responsiveness of the sensor through current-voltage based on SnO 2 nanowire films under different concentration conditions ranging was verified from 1 to 1000 mmol. UV sensors show a typical amperometric response of SnO 2 nanowires under the excitation of UV and GLU in ten cycles of 300 s with 1.0 V observing a stable and reliable amperometric response. GLU and UV sensors proved to have a promising potential for detection and to control the conversion of a substrate into a product by GLU control and decontamination by UV control in industrial fermentation systems.

Significance: Optimal skin wound healing is crucial for maintaining tissue homeostasis, particularly in response to an injury. The skin immune system is under regulation of mediators such as bioactive lipids and cytokines that can initiate an immune response with controlled inflammation, followed by efficient resolution. However, nutritional deficiency impacts wound healing by hindering fibroblast proliferation, collagen synthesis, and epithelialization, among other crucial functions. In this way, the correct nutritional support of bioactive lipids and of other essential nutrients plays an important role in the outcome of the wound healing process. Recent Advances and Critical Issues: Several studies have revealed the potential role of lipids as a treatment for the healing of skin wounds. Unsaturated fatty acids such as linoleic acid, α-linolenic acid, oleic acid, and most of their bioactive products have shown an effective role as a topical treatment of chronic skin wounds. Their effect, when the treatment starts at day 0, has been observed mainly in the inflammatory phase of the wound healing process. Moreover, some of them were associated with different dressings and were tested for clinical purposes, including pluronic gel, nanocapsules, collagen films and matrices, and polymeric bandages. Therefore, future research is still needed to evaluate these dressing technologies in association with different bioactive fatty acids in a wound healing context. Future Directions: This review summarizes the main results of the available clinical trials and basic research studies and provides evidence-based conclusions. Together, current data encourage the use of bioactive fatty acids for an optimal wound healing resolution.

Mounting evidence showing that local nitric oxide (NO) delivery may significantly improve the wound healing process has stimulated the development of wound dressings capable of releasing NO topically. Herein, we describe the preparation of a self-expandable NO-releasing hydrolyzed collagen sponge (CS), charged with the endogenously found NO donor, S-nitrosoglutathione (GSNO). We show that cold pressed and GSNO-charged CS (CS/GSNO) undergo self-expansion to its original 3D shape upon water absorption to a swelling degree of 2,300 wt%, triggering the release of free NO. Topical application of compressed CS/GSNO on wounds in an animal model showed that exudate absorption by CS/GSNO leads to the release of higher NO doses during the inflammatory phase and progressively lower NO doses at later stages of the healing process. Moreover, treated animals showed significant increase in the mRNA expression levels of monocyte chemoattractant protein-1 (MCP-1), murine macrophage marker (F4/80), transforming growth factor beta (TGF-β), stromal cell-derived factor 1 (SDF-1), insulin-like growth factor-1 (IGF-1), nitric oxide synthase(iNOS), and matrix metalloproteinase(MMP-9). Cluster differentiation 31 (CD31), vascular endothelial growth factor (VEGF), and F4/80 were measured on Days 7 and 12 by immunohistochemistry in the cicatricial tissue. These results indicate that the topical delivery of NO enhances the migration and infiltration of leucocytes, macrophages, and keratinocytes to the wounded tissue, as well as the neovascularization and collagen deposition, which are correlated with an accelerated wound closure. Thus, self-expandable CS/GSNO may represent a novel biocompatible and active wound dress for the topical delivery of NO on wounds., (© 2020 John Wiley & Sons, Ltd.)