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The increasing incidence of neurodegenerative and other diseases is considered to involve an excessive production of reactive oxygen species (ROS). Water supplies are often characterized by excessive organic waste that is decomposed by bacteria, using dissolved oxygen, leading to oxygen depletion. The potassium content of these waters may also affect negatively the mitochondrial metabolism and cellular ROS formation. This work focused on characterizing mitochondrial autofluorescence changes, with flavoprotein origin, and fluorescence ROS signals measured using the 2',7'-dichlorodihydrofluorescein diacetate indicator H2DCFDA. All signals were evoked by hypoxia or by the depolarizing agent KCl (20 mM), at the hippocampal mossy fiber synapses of CA3 area. It was observed that both hypoxia and KCl-induced depolarization elicited a small rise in the autofluorescence and ROS changes. The hypoxia-induced signals were maintained upon normal reoxygenation, but of those evoked by KCl, the autofluorescence signals recovered during washout, while the ROS changes were irreversible.

Reactive oxygen species (ROS) have an important role in cellular biology, being involved, in a way that depends on their levels, in cell signaling processes or in oxidative stress, probably associated with neurodegenerative and other diseases. Most of the studies about ROS formation were performed in ischemic conditions, and thus, there is limited knowledge about ROS formation in less severe hypoxic conditions. This study investigates neuronal ROS generation and autofluorescence changes in hypoxic conditions, focusing on the involvement of calcium and zinc. Using hippocampal slices from Wistar rats, ROS production was monitored by the permeant fluorescent indicator H 2 DCFDA under different oxygenation levels. Moderate hypoxia (40% O 2 ) led to a small ROS increase, while severe hypoxia (0% O 2 ) showed a more pronounced rise. KCl-induced depolarization significantly enhanced ROS formation, particularly under severe hypoxia. Inhibition of NMDA receptors reduced ROS generation without affecting autofluorescence, while chelation of zinc ions decreased ROS production and increased flavin adenine dinucleotide (FAD) autofluorescence. These findings suggest that, in hypoxic conditions, ROS formation is mediated by calcium entry through NMDA receptors and also by zinc influxes. Thus, these ions play a crucial role in oxidative stress, which may be related with neurodegenerative diseases associated with ROS dysregulation., 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 article., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In Brazil, agriculture consumes most of the available freshwater, especially in the Cerrado biome, where the rain cycle is marked by long periods of drought. This study, conducted at the Brazilian Agricultural Research Corporation (Embrapa) Research Corporation unit in Santo Antônio de Goiás, Goiás, Brazil, estimated evapotranspiration (ET) in different crops and soil cover. Using multispectral unmanned aerial vehicle (UAV) images, Sentinel satellite data, weather station information, and towers employing the eddy covariance method, we applied the "Simple Algorithm for Evapotranspiration Retrieving" (SAFER) to calculate ET in common bean, pasture, and semideciduous seasonal forest areas. The results showed a good agreement between UAV and satellite data, with R 2  = 0.84, also validated with flow towers by the eddy covariance method. UAV-based ET was observed to correspond well to tower (EC) during full vegetative development of beans but is underestimated at the beginning of planting and in the final periods of plant senescence, due to the influence of soil or straw cover. These findings contribute to a better understanding of water dynamics in the system and to enhancing sustainable agricultural practices. This method, adapted for multispectral aerial imaging, can be applied flexibly and on-demand, in different contexts and ground cover. The study highlights the importance of integrated agricultural practices for better management of water resources and preservation of the Cerrado in balance with cultivation areas., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Antimicrobial resistance is an increasing worldwide public health burden that threatens to make existent antimicrobials obsolete. An important mechanism of antimicrobial resistance is the overexpression of efflux pumps, which reduce the intracellular concentration of antimicrobials. TolC is the outer membrane protein of an efflux pump that has gained attention as a therapeutic target. Little is known about the immune response against TolC. Here we evaluated the immune response against TolC from Escherichia coli. TolC in silico epitope prediction showed several residues that could bind to human antibodies, and we showed that human plasma presented higher titers of anti-TolC IgG and IgA, than IgM. E. coli recombinant TolC protein stimulated macrophages in vitro to produce nitric oxide, as well as IL-6 and TNF-α, assessed by Griess assay and ELISA, respectively. Immunization of mice with TolC intraperitoneally and an in vitro re-stimulation led to increased T cell proliferation and IFNγ production, evaluated by flow cytometry and ELISA, respectively. TolC mouse immunization stimulated anti-TolC IgM and IgG production, with higher levels of IgG1 and IgG2, amongst the IgG subclasses. Anti-TolC murine antibodies could bind to live E. coli and increase bacterial uptake and elimination by macrophages in vitro. Intraperitoneal or intranasal, but not oral, immunizations with inactivated E. coli also led to anti-TolC antibody production. Finally, TolC immunization increased mouse survival rates to antimicrobial-sensitive or resistant E. coli infection. Our results showed that TolC is immunogenic, leading to the production of protective antibodies against E. coli, reinforcing its value as a therapeutic target., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for Leukocyte Biology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Introduction: Worldwide, there is an increase in scrutiny after surgical treatment of a vast array of pathologies. Doing so, a large body of evidence clearly supports centralisation, such as teaching hospitals, where a larger caseload enables optimal outcomes. These institutions have a strong presence of surgical residents seeking training in both technical and non-technical skills. Inevitably, as part of training, they will be involved in the surgical treatment of those patients, even as the primary operator. We sought to investigate the impact of trainee performed procedures in outcomes of common vascular procedures of different technical complexity., Methods: A non-systematic MEDLINE and Scopus databases review on the outcomes of resident performed common vascular procedures was performed., Results: Specific evidence in many procedures (venous disease, aortic aneurysms, peripheral artery disease) is lacking. After carotid endarterectomy (CEA), resident performed procedures seem to have similar cranial nerve palsy and stroke when compared to expert surgeons. Generally, resident-performed primary radiocephalic and elbow arteriovenous fistula (AVF) presents similar primary and secondary patency. As with CEA, AVF procedures performed by residents took longer. On aortic aneurysms, although no specific comparison has been performed, resident involvement (irrespective of surgeon or assistant) in these procedures does not seem associated with increased adverse events., Conclusion: In most vascular surgery procedures, little is known about resident performance and their impact on outcomes. Notwithstanding, resident-performed CEA and primary AVF seem free of major compromise to patients. Further research is warranted to clarify this topic.