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Tailings from iron mining are characterized by high concentrations of iron and manganese oxides, as well as high pH values. With these characteristics, most of the potentially toxic elements (PTE) contained in the tailings are somewhat unavailable. The aim of the present study was to evaluate how a reduction in the pH of iron mine tailings may affect PTE availabilities. The tailings were collected on the banks of the Gualaxo do Norte River (Mariana, MG, Brazil), one of the main areas impacted by the rupture of the Fundão Dam (Barragem de Fundão). A completely randomized experimental design was used, including five pH values (6.4, 5.4, 4.3, 3.7, and 3.4) and five replications. The concentrations of the PTE (Ba, Cr, Cd, Co, Cu, Fe, Mn, Pb, Ni, and Zn) were determined after extraction following different methodologies: USEPA 3051A, DTPA, Mehlich-1, Mehlich-3, and distilled water. A comparison of the available concentrations of the elements in the tailings with those in a soil not impacted by tailings shows that Cr, Cd, Cu, Fe, Mn, Ni, Ba, and Co were higher in the soil impacted by the tailings. The different methods used for evaluating the availability of PTE in the tailings at various pH exhibited the following decreasing order in relation to the quantity extracted: Mehlich-3 > Mehlich-1 > DTPA > distilled water. However, regarding sensitivity to change in pH, the order was DTPA > water > Mehlich-1 > Mehlich-3. The increases in the concentrations of PTE due to the reduction in the pH of the tailings did not lead to concentrations that exceed the limits of Brazilian regulations. The DTPA extractant exhibited higher coefficients of correlation between the PTE concentrations and the pH of the tailings, proving to be suitable for use in areas affected by the deposition of iron mine tailings., 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 © 2022 Elsevier Inc. All rights reserved.)

Aim: To evaluate the antifungal activity of gallic acid (GA) against the strains of Candida spp. resistant to fluconazole and to determine its mechanism of action. Materials & methods: Antifungal activity was evaluated using the broth microdilution and flow cytometry techniques. Results: GA presented minimum inhibitory concentrations ranging from 16 to 72 μg/ml, causing alterations of the membrane integrity and mitochondrial transmembrane potential, production of reactive oxygen species and externalization of phosphatidylserine. Conclusion: GA has potential antifungal activity against Candida spp.

Introduction: The devasting effects of COVID-19 have caused economic and health impacts worldwide. Anesthesiologists were one of the key professionals fighting the pandemic and have been highly exposed at their multiple sites of clinical practice. Thus, the importance of determining the nature of the infection in this population that provides care to SARS-CoV-2 patients., Method: We conducted a cross-sectional study administering an online questionnaire to examine the demographic and epidemiological profile of these professionals in Brazil, and to describe the risk factors for viral infection during the pandemic., Results: A total of 1,127 anesthesiologists answered the questionnaire, 55.2% were men, more than 90% with age below 60 years, with infection and reinfection rates of 14.7% and 0.5%, respectively, and 47.2% reported a significant income reduction. The predictors of COVID-19 contamination were practicing in operating rooms (OR = 0.42; 95% CI 0.23-0.78), direct contact with infected patients (OR = 5.74; 95% CI 3.05-11.57), indirect contact with infected patients (OR = 2.43; 95% CI 1.13-5.33), working in a pre-hospital setting (OR = 2.36; 95% CI 1.04-5.03), and presence of immunosuppression, except for cancer (OR = 4.89; 95% CI 1.16-19.01)., Conclusion: COVID-19 had enormous consequences on Brazilian anesthesiologists regarding sociodemographic aspects and contamination rates (5.57 times higher than in the general population). These are alarming and unprecedented findings for this professional group, as they reveal the considerable risk of infection and its independent predictor variables., (Copyright © 2021 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.)

The dynamic, accurate measurement of pupil size is extremely valuable for studying a large number of neuronal functions and dysfunctions. Despite tremendous and well-documented progress in image processing techniques for estimating pupil parameters, comparatively little work has been reported on practical hardware issues involved in designing image acquisition systems for pupil analysis. Here, we describe and validate the basic features of such a system which is based on a relatively compact, off-the-shelf, low-cost FireWire digital camera. We successfully implemented two configurable modes of video record: a continuous mode and an event-triggered mode. The interoperability of the whole system is guaranteed by a set of modular software components hosted on a personal computer and written in Labview. An offline analysis suite of image processing algorithms for automatically estimating pupillary and eyelid parameters were assessed using data obtained in human subjects. Our benchmark results show that such measurements can be done in a temporally precise way at a sampling frequency of up to 120 Hz and with an estimated maximum spatial resolution of 0.03 mm. Our software is made available free of charge to the scientific community, allowing end users to either use the software as is or modify it to suit their own needs., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

This research evaluated the in vitro acaricidal activity of extracts from 21 plant species from the Pantanal of Mato Grosso do Sul. During stage I, a larval immersion test was performed using three extract concentrations (5%, 20%, and 40%). During stage II, we used only plants that showed over 95% efficiency at the 40% concentration in stage I in an amount sufficient for the adult immersion test. Aeschynomene denticulata, Angelonia hirta, Aspilia latissima, Caperonia castaneifolia, Centratherum punctatum, Crotalaria micans, Diodia kuntzei, Echinodorus paniculatus, Hyptis mutabilis, Lantana canescens, Melanthera latifolia, Ocotea diospyrifolia, Richardia grandiflora, Sebastiana hispida, Tocoyena formosa, Zanthoxylum rigidum, and Sesbania virgata (fruit extract) showed acaricidal activity against the larval stage of Rhipicephalus (Boophilus) microplus higher than 95% at a 40% (w/v) concentration, while Hippocratea volubilis and Randia armata showed moderate efficacy and Croton glandulosus and Senna obtusifolia had no effect. The M. latifolia, A. hirta, R. grandiflora, and A. latissima raw extracts were evaluated for their activity against adults, and only A. hirta showed an efficacy close to 90%. Eighteen extracts had an efficacy of up to 95% against larvae at a 40% concentration, seven extracts were effective at 20%, and only one (Sebastiana hispida) was effective at a 5% concentration.

Light emitting diodes (LEDs) are extensively used as light sources to investigate visual and visually related function and dysfunction. Here, we describe the design of a compact, low-cost, stand-alone LED-based system that enables the configuration, storage and presentation of elaborate visual stimulation paradigms. The core functionality of this system is provided by a microcontroller whose ultra-low power consumption makes it well suited for long lasting battery applications. The effective use of hardware resources is managed by multi-layered architecture software that provides an intuitive and user-friendly interface. In the configuration mode, different stimulation sequences can be created and memorized for ten channels, independently. LED-driving current output can be set either as continuous or pulse modulated, up to 500 Hz, by duty cycle adjustments. In run mode, multiple-channel stimulus sequences are automatically applied according to the pre-programmed protocol. Steady state visual evoked potentials were successfully recorded in five subjects with no visible electromagnetic interferences from the stimulator, demonstrating the efficacy of combining our prototyped equipment with electrophysiological techniques. Finally, we discuss a number of possible improvements for future development of our project., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The nitric oxide produced by endothelial nitric oxide synthase (eNOS) plays a pivotal role in protecting the arterial wall from damages and atherosclerosis. The T-786C, the 27-bp repeat in intron 4, and the E298D eNOS gene polymorphisms were studied in 715 Brazilian patients (447 Caucasian- and 268 African-Brazilians) who underwent coronary angiography. The -786C frequency was increased in coronary artery disease (CAD) cases with significant lesions (> or =50% luminal obstruction) when compared with lesion-free controls; this difference was detected in smokers but not in nonsmokers, both in Caucasian- (p=0.011) and African-Brazilians (p=0.005). The interaction between -786C carriers and smoking was an independent CAD predictor (OR: 2.9, 95% CI: 1.4-5.9; p=0.003) in multiple logistic regression. The 298D mutation frequency was also higher among CAD cases (p=0.036) in African-Brazilian smokers, but this effect was not independent from other variables in the regression model. Though not associated with CAD, the 4-repeat allele combined with different T-786C alleles showed protective and susceptible effects in Caucasian-Brazilian smokers. The -786C/4-repeat/298E haplotype frequency was higher (p=0.020), whereas -786T/4-repeat/298E was lower (p=0.023) in these cases. These results showed a smoking-dependent effect of the T-786C eNOS polymorphism on CAD in both Caucasian- and African-Brazilians. Additionally, the haplotype analysis revealed different eNOS haplotypes associated with protection and susceptibility to the disease.

Extensive and severe myocardial lesions are reported in a patient who died due to snakebite (Crotalus Durissus Terrificus). These lesions are documented by clinical, electrocardiographic, enzymatic and histological evidences. The main pathological features are represented by sarcoplasmatic vacuoles, densely clumped myofibrils and amorphous acidophilic mass into the cardiac fibers. These lesions are identical to those which have already been described in skeletal muscle after snakebite. This seems to be the first case report that shows undoubt myocardial lesions due to snakebite with anatomopathological documentation.