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BACKGROUND: Methylmercury (MeHg) and ethylmercury (EtHg) are potent toxicants affecting the environment and human healthy. In this way, the present study aimed to investigate and compare the effects of MeHg and EtHg exposure on human peripheral blood mononuclear cells (PBMCs), which are critical components of the mammalian immune system. METHODS: PBMCs were exposed to 2.5 µM MeHg or 2.5 µM EtHg. The number of cells and incubation times varied according to each assay. After exposures, the PBMCs were subjected to different evaluations, including cell viability, morphological aspects, cell cycle phases, indices of apoptosis and necrosis, reactive species (RS) production, and mitochondrial functionality. RESULTS: PBMCs exposed to EtHg were characterized by decreased viability and size, increased granularity, RS production, and apoptotic indexes accompanied by an intensification of Sub-G1 and reduction in G0-G1 cell cycle phases. Preceding these effects, we found mitochondrial dysfunctions, namely a reduction in the electron transport system related to mitochondrial complex I. In contrast, PBMCs exposed to MeHg showed only reduced viability. By ICP-MS, we found that PBMCs treated with EtHg accumulated Hg + levels â¼1.8-fold greater than MeHg-exposed cells. CONCLUSIONS AND SIGNIFICANCE: Taken together, our findings provide important insights about mercury immunotoxicity, showing that EtHg is more immunotoxic to human PBMCs than MeHg.
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Mercurio , Compuestos de Metilmercurio , Animales , Humanos , Compuestos de Metilmercurio/toxicidad , Leucocitos Mononucleares , Mitocondrias , Estrés Oxidativo , MamíferosRESUMEN
OBJECTIVE: Areas of the foot with diabetic ulcers have been observed to have greater plantar pressures compared to non-ulcerated. Pressures play an essential role in the mechanism of lesion, and their reduction is effective in prevention. We conducted a systematic review to evaluate pedobarography as a predictive tool for ulcer development, since there is still no consensus on this aspect. METHODS: We searched PUBMED (MedLine), EMBASE, Scopus, Web of Science, CINAHL and Scielo for cohort studies that measured plantar pressure at baseline and verified ulcer development on follow-up. Pooled effects of accuracy, sensitivity, specificity and relative risk were calculated using the inverse variance method. Risk of bias was assessed using the QUADAS-2 tool. RESULTS: Three studies (n = 2000) had enough information on accuracy to be included into a meta-analysis, and 4 (n = 2651) were analyzed using qualitative methods. Pooled sensitivity and specificity were found to be 0.63 (Confidence Interval (CI) 0.58-0.68) and 0.42 (CI 0.27-0.58), respectively. Pooled relative risk was 1.95 (CI 1.09-3.51). Risk of bias was low to uncertain. CONCLUSIONS: Pedobarography in itself appears to have low accuracy in evaluating risk of ulceration. Several methodological heterogeneities were found, and the most optimal cut-off value is yet to be determined.
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Diabetes Mellitus , Pie Diabético , Úlcera del Pie , Humanos , Pie Diabético/prevención & control , Pie , Sensibilidad y Especificidad , PresiónRESUMEN
Indoor air quality (IAQ) problems in school environments are very common and have significant impacts on students' performance, development and health. Indoor air conditions depend on the adopted ventilation practices, which in Mediterranean countries are essentially based on natural ventilation controlled through manual window opening. Citizen science projects directed to school communities are effective strategies to promote awareness and knowledge acquirement on IAQ and adequate ventilation management. Our multidisciplinary research team has developed a framework-SchoolAIR-based on low-cost sensors and a scalable IoT system architecture to support the improvement of IAQ in schools. The SchoolAIR framework is based on do-it-yourself sensors that continuously monitor air temperature, relative humidity, concentrations of carbon dioxide and particulate matter in school environments. The framework was tested in the classrooms of University Fernando Pessoa, and its deployment and proof of concept took place in a high school in the north of Portugal. The results obtained reveal that CO2 concentrations frequently exceed reference values during classes, and that higher concentrations of particulate matter in the outdoor air affect IAQ. These results highlight the importance of real-time monitoring of IAQ and outdoor air pollution levels to support decision-making in ventilation management and assure adequate IAQ. The proposed approach encourages the transfer of scientific knowledge from universities to society in a dynamic and active process of social responsibility based on a citizen science approach, promoting scientific literacy of the younger generation and enhancing healthier, resilient and sustainable indoor environments.
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Contaminación del Aire Interior , Contaminación del Aire , Ciencia Ciudadana , Humanos , Aire Acondicionado , Material ParticuladoRESUMEN
Oxidized LDL (oxLDL) plays a pivotal role on atherosclerosis development, mainly in the formation of lipid-laden macrophage "foam cells". As a consequence, substances that can modulate LDL oxidation have a pharmacological and therapeutic relevance. Based in previous findings showing the ability of Syzigium cumini leaf extract (ScExt) in preventing LDL oxidation in vitro, this study was aimed to assess the effects of ScExt on oxLDL-mediated toxicity in murine J774 macrophages-like cells. For biochemical analyses, LDL isolated from fresh human plasma and oxidized with CuSO4 was incubated with ScExt pre-treated macrophages. Our results demonstrated that ScExt was efficient in preventing the overproduction of reactive oxygen/nitrogen species (ROS/RNS), the loss of macrophage's viability and the foam cells formation induced by oxLDL. These protective effects of ScExt make it a promising antioxidant for future trials toward atherogenesis.
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Antioxidantes/farmacología , Aterosclerosis/prevención & control , Macrófagos/efectos de los fármacos , Extractos Vegetales/farmacología , Hojas de la Planta/química , Sustancias Protectoras/farmacología , Syzygium/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células Espumosas/citología , Células Espumosas/efectos de los fármacos , Humanos , Lipoproteínas LDL/toxicidad , Ratones , Especies Reactivas de Oxígeno/metabolismoRESUMEN
A heavy particle impact vibrational excitation and dissociation model for CO2 is presented. This state-to-state model is based on the forced harmonic oscillator (FHO) theory, which is more accurate than current state-of-the-art kinetic models of CO2 based on first-order perturbation theory. The first excited triplet state 3B2 of CO2, including its vibrational structure, is considered in our model, and a more consistent approach to CO2 dissociation is also proposed. The model is benchmarked against a few academic zero-dimensional (0D) cases and compared to decomposition time measurements in a shock tube. Our model is shown to have reasonable predictive capabilities, and the CO2 + O â CO + O2 reaction is found to have a key influence on the dissociation dynamics of CO2 shocked flows, warranting further theoretical studies. We conclude this study with a discussion on the theoretical improvements that are still required for a more consistent analysis of the vibrational/dissociation dynamics of CO2.
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INTRODUCTION: Aging is characterized by reductions in lean mass simultaneously to increases in visceral adipose tissue, elevating cardiovascular risk (CVR) and physical dependence. Dancing has been recommended for improving fall-risk and CVR, however, comparisons with traditional exercises are limited. This study aimed to compare the effects of dancing with walking on CVR and functionality of older women. METHODS: Thirty sedentary women (65⯱â¯5â¯years, BMI 27⯱â¯4â¯kg/m2) were randomized into three groups (nâ¯=â¯10/group): dancing, walking or stretching (active control). All interventions lasted 8â¯weeks (60â¯min sessions): dancing/walking 3×/week, stretching 1×/week. Dancing: several styles, no partner. Walking: treadmill, 60% peak oxygen consumption (VO2peak). Stretching: large muscle groups, no discomfort. Before and after interventions assessments: VO2peak (primary outcome), total cholesterol, HDL-C, LDL-C, glucose, insulin, CRP, TNF-α, waist and hip circumferences, visceral adipose tissue (VAT), muscle thickness, maximal muscle strength/power, static and dynamic balance, gait ability, flexibility, chair-raise and level of physical activity (PA). STATISTICS: generalized estimating equations, post-hoc LSD (pâ¯<â¯0.05), SPSS 22.0. RESULTS: (Mean-CI): (before vs after): group vs time interaction showed increases in VO2peak (mL·kg-1·min-1) for dancing 23.3 (20.8-25.8) vs 25.6 (23.4-27.8), and walking 23.4 (21.3-25.5) vs 27.0 (25.4-28.6), with no differences for stretching 23.5 (21.3-25.7) vs 23.0 (21.0-24.9). Lower body muscle power and static balance also improved for dancing and walking, but not for stretching. Main time effect showed improvements in CRP, TNF-α, LDL-C, HDL-C, VAT, waist, hip, chair raise, flexibility and level of daily PA for all groups. CONCLUSION: Dancing induced similar increases in VO2peak, lower body muscle power and static balance as walking, while the stretching group remained unchanged. Pooled effects showed improvements in body composition, lipid and inflammatory profile, which are supported by increased PA levels. TRIAL REGISTRATION: NCT03262714.
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Enfermedades Cardiovasculares/fisiopatología , Baile/fisiología , Caminata/fisiología , Anciano , Brasil , Prueba de Esfuerzo , Femenino , Humanos , Persona de Mediana Edad , Fuerza Muscular , Consumo de Oxígeno , Equilibrio PosturalRESUMEN
This study investigated the influence of performing strength exercises before or after high-intensity interval exercise on glycaemia during and postexercise in T1DM patients. Nine physically active adults with T1DM executed 30 min of strength exercises (SE) (3 sets at 10 RM) before 30 min of high-intensity interval exercise (HIIE) (10 × 60-s bout at â¼90% HRmax interspersed with 60 s recovery) (SE + HIIE) or performed the reverse order (HIIE + SE) or rested in this period. Capillary glucose levels were measured each 15 min during and 60 min postexercise recovery. Significant lower glucose levels were observed in SE + HIIE at 60, 75 and 90 min, in comparison with REST. HIIE + SE lowered glycaemia at 30, 45 and 60 min compared with baseline concentrations, while SE + HIIE postponed this glucose decayment to 60 min, when compared with baseline levels. An increased glycaemia at 105 min compared with end-exercise levels were also observed in HIIE + SE. Carbohydrates ingested during exercise to correct hypoglycemia, insulin dosage at same day before and after protocols, and nocturnal hypoglycemia episodes were similar among the three conditions. It is concluded that the performance of HIIE before SE decreases glycaemia already at the end of first exercise modality, while the reverse order postpones it to the end of second exercise, although HIIE + SE improves glycemic stability throughout recovery. T1DM patients who tend to develop exercise-associated hypoglycemia may perform strength exercises before high-intensity interval exercise in a single session.
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Glucemia/fisiología , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/terapia , Terapia por Ejercicio , Adolescente , Adulto , Glucemia/análisis , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Femenino , Humanos , Hipoglucemia/prevención & control , Insulina/uso terapéutico , Masculino , Adulto JovenRESUMEN
PURPOSE: Flattening of oxygen pulse curve during incremental cardiopulmonary exercise testing has been proposed for the improvement of diagnostic accuracy of exercise-induced myocardial ischemia. In this study, we compare the oxygen pulse response to incremental treadmill exercise in patients with and without ischemia as detected by myocardial perfusion scintigraphy. METHODS: Eighty-seven patients referred to exercise myocardial perfusion scintigraphy were also evaluated with incremental treadmill cardiopulmonary exercise testing. One investigator prospectively identified patients who presented transient exercise-induced perfusion defects on 99mTc sestamibi myocardial scintigraphies. Another investigator evaluated the response of oxygen pulse to incremental exercise testing without knowledge of electrocardiographic response or scintigraphic findings. RESULTS: Exercise myocardial perfusion scintigraphy detected transient perfusion defects in 36% of the patients. Compared with patients with normal perfusion studies, patients with exercise-induced ischemia presented similar peak double product, peak oxygen uptake, and anaerobic threshold. Oxygen pulse at 25% of peak (ischemia: 9.7 +/- 2 mL per beat; no ischemia: 9.3 +/- 2 mL per beat), 50% of peak (11.2 +/- 3 vs 10.8 +/- 3 mL per beat), 75% of peak (12.5 +/- 3 vs 11.9 +/- 3 mL per beat), and at peak exercise (13 +/- 4 vs 13 +/- 4 mL per beat) were not different in exercise-induced ischemia and normal groups, respectively. However, patients who presented extensive transient perfusion defects during exercise had a lower peak oxygen pulse (12.8 +/- 3.8 vs 16.4 +/- 4.6 mL per beat; P < 0.05). CONCLUSION: The analysis of the oxygen pulse response to incremental exercise test does not identify mild myocardial ischemia. Flattening of oxygen pulse response during incremental exercise might be present only with extensive myocardial ischemia.