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INTRODUCTION: Piloting an aircraft is a complex multitasking activity that involves managing information in a nonautomatic way and generates a high workload (psychological, cognitive, and physical) for the pilot. The excess of these demands can result in decreased performance and may impair flight safety. Heart rate variability (HRV) has been used in recent studies as a method to investigate operator's workload in complex environments. This measure can assess the stress and recovery ability of the autonomic nervous system. However, a better understanding of flight influence on the pilot's autonomic modulation is necessary. Therefore, this scoping review aims to systematically map the studies related to changes in the autonomic modulation in military pilots during flight, in order to characterize their workload at different times and flight profiles. MATERIALS AND METHODS: A literature search was conducted using MEDLINE (by PubMed), SCOPUS, and LILACS databases. Recent records (2002-2022) that analyzed HRV in military pilots during flight were included. Meanwhile, studies in which piloting activity was not performed were excluded. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline extension for Scoping Reviews and the Updated Methodological Guidance for the Conduct of Scoping Reviews. RESULTS: A total of 298 records were obtained, of which 19 were included in the scoping review. The studies analyzed flights performed in high- and low-performance aircrafts, helicopters, and flight simulators, using time domain, frequency domain, and nonlinear HRV indices. Real and simulated flights produced significant autonomic changes. Some flights elicited autonomic nervous system responses that persisted up to 5 h after landing. During real flight, the most sensitive indices for identifying variations in pilot workload were root mean square of successive differences between normal heartbeats, standard deviation of interbeat interval of normal sinus beat (SDNN), ratio of low-frequency to high-frequency power, and Poincaré plot standard deviation perpendicular to the line of identity (SD1), whereas the interbeat interval (RR), SDNN, SD1, and Poincaré plot standard deviation along the line of identity (SD2) were the most sensitive indices when comparing segments of simulated flight with different levels of difficulty. CONCLUSIONS: This scoping review provided insight into the influence of flight on autonomic modulation in military pilots. Some key themes were highlighted: Increased sympathetic activity during flight, sensibility of different domains of HRV to flight demands, and autonomic changes during recovery time. Future research efforts may allow us to enhance the understanding of pilot's workload limits and to elucidate the optimal postflight recovery time.

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Reservoir construction promotes many environmental impacts, including the enhancement of mercury concentrations in fish. The processes that can influence mercury concentrations in fish in Amazonian reservoirs are still little explored in depth, especially when we consider the possible particularities of the ecosystems in question. This study aims to investigate how mercury concentrations in fish could be influenced by the Tucuruí dam, considering possible changes in their feeding and trophic position according to the dam position (up or downstream). Fish were sampled upstream and downstream of the Tucuruí reservoir, and total mercury (THg) and stable isotopes of carbon and nitrogen (δ15N and δ13C) were measured in muscles. We observed three different Hg bioaccumulation patterns influenced by the dam. These differences occurred due to species trophic niche changes corroborated by the isotope analysis. Higher THg concentrations downstream compared to those upstream ones were only observed for Geophagus proximus. On the contrary, Plagioscion squamosissimus, from downstream, presented lower concentrations than upstream ones. The isotopic niche of these two species presented different changes according to the sampled site. THg biomagnification was higher upstream compared to downstream, considering that the regression slope was approximately two times higher upstream versus downstream. THg concentrations in fish were explained by the differences in their feeding habits according to their location in relation to the dam. The difference in THg biomagnification was able to reflect differences in structure of the food web chain in ecosystems under the dam's influence.

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Aquatic macrophytes are the main autochthonous component of primary production in the Amazon Basin. Floating meadows of these plants support habitats with highly diverse animal communities. Fishes inhabiting these habitats have been assumed to use a broad range of food items and compose a particular food web. We employed carbon (δ13C) and nitrogen (δ15N) stable isotope analysis to draw the trophic structure of these habitats and to trace the energy flow by its trophic levels. Fishes and other animals from 18 independent macrophyte meadows of a floodplain lake of the Solimões River (Amazonia, Brazil) were analyzed. The food web of macrophyte meadows consists of four trophic levels above autotrophic sources. In general, primary consumers exhibited a broader range of food sources than the upper trophic levels. Some fish species depended on a large number of food sources and at the same time are consumed by several predators. The energy transfer from one trophic level to the next was then mainly accomplished by these species concentrating a high-energy flux and acting as hubs in the food web. The broad range of δ13C values observed indicates that the organisms living in the macrophyte meadows utilize a great diversity of autotrophic sources.

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Veterinary care for rabbits has been growing, and, consequently, the anesthetic and analgesic management of this species must be improved. The aim of the present study was to evaluate the technique of localization of the epidural space with the aid of a peripheral nerve stimulator and epidurographic, comparing two techniques for determining the infused volume in rabbits (Oryctolagus Cuniculus). In a prospective, randomized blinded study, six healthy New Zealand rabbits, adults, and weighing from 2.2 kg to 3.8 kg received two treatments, at 1 week intervals: 0.33 mL/kg (treatment I) or 0.05 mL per centimeter of the spine (treatment II) of ioexol epidurally. In both treatments, a peripheral nerve stimulator (2 Hz, 0.25 mA and 0.1 milliseconds) was used to determine the location of the epidural space. Latero-lateral and ventro-dorsal radiographs were taken after five (T5) and twenty-five minutes (T25) of iohexol administration. The epidural space was correctly accessed in 92% of attempts. Treatment I received a smaller volume of contrast than treatment II, 1.0 ± 0.2 mL versus 2.1 ± 0.1 mL (mean ± standard deviation), respectively (p = 0.007). At T5, the cranial progression of the contrast varied between L4 and L5 in treatment I, and L5 and T10 in treatment II. At T25, no contrast was observed in any rabbit. In conclusion, peripheral nerve stimulator aided in accessing the lumbosacral epidural space, and the administration of 0.05 mL per centimeter of the spine resulted in greater cranial progression of contrast.

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INTRODUCTION: Sporotrichosis, a zoonosis caused by animal, mainly cat, scratches or bites, is caused by fungi belonging to the Sporothrix complex. Treatment usually consists in antifungal administration, although treatment failure and hepatotoxicity reports have been noted. Alternative sporotrichosis treatment methods, such as antimicrobial photodynamic therapy (aPDT), may, therefore, be indicated. CASE REPORT: In this context, this study followed a 56-year-old male renal transplanted patient displaying disseminated sporotrichosis, presenting erythematous skin lesions with ulcerated backgrounds and hardened consistency on the nose, oral and scalp. The lesions were present for about 2 months and the patient coexisted with cats. Intravenous amphotericin B administration was initiated, and immunosuppression was suspended. Seven aPDT sessions were also performed in 48 h intervals on the oral lesions, employing 0.01% methylene blue gel as the photosensitizing agent. After the 4th aPDT session, the patient was discharged, amphotericin B administration was suspended, and the treatment was continued with itraconazole, without immunosuppression. Red laser was applied to the oral lesions after the 7th aPDT session. Significant lesion improvement was observed after the final aPDT session and complete palate lesion repair was noted after two red laser sessions. CONCLUSION: These findings indicate that aPDT is a valuable strategy as an adjunct sporotrichosis treatment.

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The Paraíba do Sul River (PSR) Basin is a crucial drainage basin in Southeast Brazil, being the most industrialized and densely populated region in the country. Over the last three decades, the basin has been the subject of numerous studies due to its long history of mercury (Hg) contamination. This makes the PSR Basin an excellent model to evaluate Hg cycling, which is a priority for signatory countries of the Minamata Convention, which includes Brazil. This review compiled data on Hg from five environmental compartments (animals, plants, sediment, suspended particulate matter (SPM), and water), three different sectors (upper, middle, and lower) and five different ecosystems (reservoir, mangrove, fluvial, estuarine, and coastal) from 60 published studies, aiming to understand the Hg cycling through meta-analyses. The highest concentrations of Hg were observed in the upper and middle sectors of the basin, which are areas with high industrialization and urbanization levels. Among the evaluated ecosystems, hydropower reservoirs showed the highest medians and were also frequent in the upper and middle portions of the PSR basin. Over the years, all environmental compartments showed a decline in Hg concentrations due to the implementation of federal and state environmental policies. The main source of Hg for the basin was Hg-rich soils from past activities (such as artisanal small-scale gold mining and the use of organomercurial fungicides in sugarcane plantations). These results can assist decision-makers in the management of the basin's ecosystems and can also be used to evaluate the effectiveness of implementing the Minamata Convention in the region.

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In this study, we measured Ni, Co, Cd, and Pb concentrations in the whole blood of farmers from southeast Brazil to address the factors influencing human exposure in this population. The factors included smoking, alcohol consumption, aging, body composition, gender, and feeding preferences, which were measured through carbon and nitrogen isotopic composition. We also calculated and compared the reference values (RVs) of the measured elements to evaluate ongoing exposure levels. We observed the influence of lifestyle habits on metal exposure; Cd levels were statistically higher in smokers, and alcohol consumption affected only Pb concentrations, with an association also observed with the frequency of alcohol ingestion. The metal levels were positively associated with both isotope values, indicating that feeding may be the dominant source of these elements in this population. We also observed the effect of endogenous sources measured through age, as increased Pb concentrations in both genders and higher Cd levels in older women, which is related to bone, kidney, and liver accumulation. The body mass index was negatively associated with Ni, Co, and Cd in women and positively in men. The negative associations may indicate that body fat may act as a reservoir for metals, reducing their availability in the blood in individuals with higher body mass and possibly influencing the assessment of exposure levels. The evaluated population presented elevated RVs for all elements: Ni 36, Co 3.3, Cd 16, and Pb 149 µg L-1. These values point to higher exposure in this population compared to other studies in Brazil and worldwide. These results emphasize an urgent need for monitoring programs for toxic substances in Brazil and evaluating possible health effects, given the ongoing environmental exposure associated with endogenous exposure and lifestyle habits that promote higher metal levels in this population.

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Titanium with nanotopography (Ti Nano) favors osteoblast differentiation and attenuates the osteoclast inhibitory effects on osteoblasts. Because the interactions between nanotopography and osteoclasts are underexplored, the aims of this study were to evaluate the effects of Ti Nano on osteoclast differentiation and activity, and the influence of osteoblasts on osteoclast-Ti Nano interaction. The discs were conditioned with a mixture of 10 N H2SO4 and 30% aqueous H2O2 to create Ti Nano and non-conditioned Ti discs were used as control (Ti Control). Osteoclasts were cultured on Ti Control and Ti Nano in the presence of osteoblasts in an indirect co-culture system. Also, osteoclasts were cultured on polystyrene and calcium phosphate plates in conditioned media by osteoblasts grown on Ti Control and Ti Nano. While Ti Control exhibited an irregular and smooth surface, Ti Nano presented nanopores distributed throughout the whole surface. Additionally, anisotropy was higher on Ti Nano than Ti Control. Nanotopography favored the gene expression of osteoclast markers but inhibited osteoclast differentiation and activity, and the presence of osteoblasts enhanced the effects of Ti Nano on osteoclasts. Such findings were mimicked by conditioned medium of osteoblasts cultured on Ti Nano, which reduced the osteoclast differentiation and activity. In conclusion, our results indicated that nanotopography regulates osteoblast-osteoclast crosstalk and further investigations should focus the impact of these bone cell interactions on Ti osseointegration.

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The Brazilian sardine (Sardinella aurita) is an important food resource found in the subtropical Southwestern Atlantic Continental Shelf (CSSWA), but limited information about its metal(loid) concentrations is available, restricting effective risk assessment by its consumption. On this research, we hypothesized that S. aurita presents different metal(loid) concentrations within a latitudinal gradient in the CSSWA (northern and southern sectors). We also assessed the S. aurita consumption contamination risk in both sectors of the CSSWA. The results indicated that S. aurita might present different chemical and contamination profiles between the observed sectors, with highlights to As, Cr, and Fe at greater levels than the safety limits established by regulatory agencies. Such finds could be explained by urbanization, industrialization, continental and oceanographic processes along the CSSWA, corroborating our hypothesis for most observed metals(loid). On the other hand, our risk assessment analysis of metal(loid) concentrations did not indicate hazards for human consumption.

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Paciente masculino, 38 anos, tabagista ativo e usuário de crack com diagnóstico recente de cardiomiopatia dilatada com fração de ejeção reduzida, dá entrada no pronto socorro com queixa de dispneia classe funcional IV, edema de membros inferiores, extremidades frias, ortopneia e dispneia paroxística noturna de início há quatro dias da admissão. Afirma tratamento para tromboembolismo pulmonar e AVE isquêmico há 06 meses. Nega precordialgia ou outros sinais e sintomas. Iniciado então tratamento para insuficiência cardíaca descompensada, com necessidade de inotrópico e noradrenalina para estabilidade hemodinâmica. Realizado ecocardiograma transtorácico e evidenciada disfunção biventricular importante (FEVE = 16% e FAC = 16%), com imagem ecogênica sugestiva de hematoma intramiocárdico dissecante na parede inferior do ventrículo esquerdo, acinesia da parede anterior e hipocontratilidade das demais paredes do ventrículo esquerdo, associada a imagem sugestiva de trombo atapetando a parede anterior e estendendo-se até a região apical do ventrículo esquerdo. Realizada tomografia computadorizada do coração com realce tardio que evidenciou infarto do miocárdico de parede inferior em todas as porções e inferolateralmediobasal, sem viabilidade. Não se observou curva de biomarcadores de necrose miocárdica. Iniciado então tratamento para insuficiência cardíaca descompensada, com necessidade de inotrópico e noradrenalina para estabilidade hemodinâmica. Paciente aguardava compensação clínica e posterior discussão de abordagem cirúrgica. Realizado novo estudo ecocardiográfico transtorácico após 07 dias, com paciente em melhora clínica dos sintomas, já sem uso de inotrópicos, onde evidenciou-se: disfunção biventricular importante (FEVE = 23% e FAC = 20%), com presença de trombo preenchendo todo o interior do aneurisma dissecante da parede inferior. Uma vez da compensação clínica e alto risco de morbimortalidade com abordagem cirúrgica desses casos, optou-se por tratamento clínico com anticoagulante e medidas para insuficiência cardíaca. Após 21 de internação, paciente recebeu alta hospitalar, assintomático para seguimento ambulatorial. O aneurisma dissecante do ventrículo esquerdo é uma condição clínica rara e que está relacionada a alta morbimortalidade pelos relatos descritos na literatura médica.

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