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•Polyethylene microplastic (PE MPs) induz induces erythrocytaries mutagenicity.•P. cuvieri exposed to PE MPs morphological abnormalities that compromise your health.•Cytotoxicity ...caused by PE MPs is demonstrated by morphometric changes in erythrocytes.•PE MPs bioaccumulate in gills, gastrointestinal tract, liver, among others.
Microplastics (MPs) are critical emerging pollutants found in the environment worldwide; however, its toxicity in aquatic in amphibians, is poorly known. Thus, the aim of the present study is to assess the toxicological potential of polyethylene microplastics (PE MPs) in Physalaemus cuvieri tadpoles. According to the results, tadpoles’ exposure to MP PE at concentration 60 mg/L for 7 days led to mutagenic effects, which were evidenced by the increased number of abnormalities observed in nuclear erythrocytes. The small size of erythrocytes and their nuclei area, perimeter, width, length, and radius, as well as the lower nucleus/cytoplasm ratio observed in tadpoles exposed to PE MPs confirmed its cytotoxicity. External morphological changes observed in the animal models included reduced ratio between total length and mouth-cloaca distance, caudal length, ocular area, mouth area, among others. PE MPs increased the number of melanophores in the skin and pigmentation rate in the assessed areas. Finally, PE MPs were found in gills, gastrointestinal tract, liver, muscle tissues of the tail and in the blood, a fact that confirmed MP accumulation by tadpoles. Therefore, the present study pioneering evidenced how MPs can affect the health of amphibians.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Field studies evaluating the influence of different soils on the efficiency of anaerobic digestates (AD) are scarce.•The focus of the work was to evaluate the soil effects on crop growth after AD ...application combined with mineral fertilizer.•The soil post-harvest properties were also examined.•Overall, the application of acidified and injected AD was as effective as nitrogenous mineral fertilizer.
Field studies evaluating the efficiency of anaerobic digestates (AD) as fertilizers often present variable results, mainly due to the effects of weather, site, soil conditions, and differences in the application technique. To better understand the soil influence on the effects of AD application on crop growth, we excluded site-specific effects of weather conditions and application technique and their interaction. A two-year experiment was conducted in southeast Germany, where pits were excavated in the field and re-filled with soils from seven Bavarian regions. Winter wheat followed by spring wheat was grown on the plots. The fertilized treatments were (i) mineral fertilizer alone (MIN), (ii) acidified anaerobic digestate plus mineral fertilizer application (ADM), and (iii) an unamended control treatment. Fertilized plots received nitrogen split into three dressings, amounting to 40-100−40 N kg ha−1 based on the NH4+ content. In the ADM treatment, the AD was applied in the second dressing, interspersed with mineral fertilization in the first and third dressings. Treatments were applied to the same plots in both years. Results showed that in the 1st-experimental year, the soil influence on crop parameters was more pronounced compared to the second year. The principal component analysis revealed that yield and grain number per spike were higher related to soil characteristics. The apparent nitrogen utilization based on the NH4+ content negatively correlated with the soil’s initial amount of mineral nitrogen. In the 2nd-experimental year, the effect of different fertilizer sources was more evident, and a trendy higher global effect on the crop parameters could be perceived in soils amended with the ADM treatment compared to those receiving only mineral fertilizers. Overall, the application of acidified and injected anaerobic digestate combined with mineral fertilizer was as effective as solely mineral nitrogen fertilizer application, with applied nitrogen based on the ammonium content, and the effect of different soils in the actual year of anaerobic application varied not markedly.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract Objective To evaluate the effect of 4 weeks of pulmonary rehabilitation (PR) versus chest physical therapy (CPT) on the preoperative functional capacity and postoperative respiratory ...morbidity of patients undergoing lung cancer resection. Design Randomized single-blinded study. Setting A teaching hospital. Participants Patients undergoing lung cancer resection (N=24). Interventions Patients were randomly assigned to receive PR (strength and endurance training) versus CPT (breathing exercises for lung expansion). Both groups received educational classes. Main Outcome Measures Functional parameters assessed before and after 4 weeks of PR or CPT (phase 1), and pulmonary complications assessed after lung cancer resection (phase 2). Results Twelve patients were randomly assigned to the PR arm and 12 to the CPT arm. Three patients in the CPT arm were not submitted to lung resection because of inoperable cancer. During phase 1 evaluation, most functional parameters in the PR group improved from baseline to 1 month: forced vital capacity (FVC) (1.47L 1.27–2.33L vs 1.71L 1.65–2.80L, respectively; P =.02); percentage of predicted FVC (FVC%; 62.5% 49%–71% vs 76% 65%–79.7%, respectively; P <.05); 6-minute walk test (425.5±85.3m vs 475±86.5m, respectively; P <.05); maximal inspiratory pressure (90±45.9cmH2 O vs 117.5±36.5cmH2 O, respectively; P <.05); and maximal expiratory pressure (79.7±17.1cmH2 O vs 92.9±21.4cmH2 O, respectively; P <.05). During phase 2 evaluation, the PR group had a lower incidence of postoperative respiratory morbidity ( P =.01), a shorter length of postoperative stay (12.2±3.6d vs 7.8±4.8d, respectively; P =.04), and required a chest tube for fewer days (7.4±2.6d vs 4.5±2.9d, respectively; P =.03) compared with the CPT arm. Conclusions These findings suggest that 4 weeks of PR before lung cancer resection improves preoperative functional capacity and decreases the postoperative respiratory morbidity.
High blood pressure is the leading risk factor to development of cardiovascular disease worldwide. Diuretic and angiotensin‐converting enzyme blockers treatment is widely used for its efficiency in ...reducing blood pressure (BP). Combined physical training (aerobic + resistance) is recommended for hypertensive patients; however, it is not yet clear whether the combination of antihypertensive treatment with this training modality results in additional benefits. Therefore, the aim of this study was to compare the effects of combined training with different drug treatments on systolic BP (SBP) and baroreflex sensitivity (BRS) of spontaneously hypertensive rats (SHR). Twenty‐eight males SHR rats were divided into four groups (n=7/group): HS (sedentary hydrochlorothiazide), HT (trained hydrochlorothiazide), ES (sedentary enalapril) and ET (trained enalapril). Drugs were administered in drinking water (enalapril 3 mg/kg/day and hydrochlorothiazide 30 mg/kg/day). All groups underwent exercise testing before and after 2 months. The trained groups performed combined training 3 times a week, being aerobic and resistance at same session, moderate intensity. The SBP was analyzed by caudal plethysmography before starting the drugs and 24h after the last training session. BRS was analyzed by response to phenylephrine and sodium nitroprusside. Both trained groups increased maximal aerobic exercise test (p<0.0001) and resistance exercise test (HT vs. HS, p=0.02; ET vs. ES, p<0.0001) versus the sedentary groups at the end of the protocol. There was no difference in the initial SBP between the groups (HS 176 ± 4.3, HT 175 ± 3, ES 173 ± 1.4 and ET 183 ± 3 mmHg). There were reductions in SBP in the HT (161 ± 1.3 mmHg), ES (159 ± 4.4 mmHg) and ET groups (147 ± 3.3 mmHg) at the end of the protocol. In addition, the trained group associated with enalapril treatment further reduced SBP when compared to the trained hydrochlorothiazide group (ET vs. HT, p = 0.02). Regarding BRS, there was no difference in tachycardic response between groups; however, ET group (‐2.8 ± 0.5 bpm/mmHg) showed increased bradycardic responses comparing with ES group (‐1.8 ± 0.1 bpm/mmHg). Therefore, the data support that the association of combined exercise training with enalapril treatment and is more effective in reducing SBP and improving BRS than the combination with hydrochlorothiazide treatment. It is noteworthy that the training proposed in this study was performed only three times a week, getting closer to clinical recommendations, and being enough for induce additional benefits to classical drug therapies in functional capacity and blood pressure control in an experimental model of hypertension.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
5.
Mercury: What can we learn from the Amazon? Crespo-Lopez, Maria Elena; Augusto-Oliveira, Marcus; Lopes-Araújo, Amanda ...
Environment international,
January 2021, 2021-01-00, 20210101, 2021-01-01, Volume:
146
Journal Article
Peer reviewed
Open access
•Approximately 80% of mercury emissions in South America is from the Amazon.•Biomass burning in the last two years will likely increase mercury exposure globally.•Mega-dams in the Amazon could be ...contributing to high levels of methylation.•Exposure of the Amazonian populations is 2–6 times the reference doses.•Actions in the Amazon carry the potential to have global repercussions.
Mercury is among the ten most dangerous chemicals for public health, and is a priority concern for the 128 signatory countries of the Minamata Convention. Mercury emissions to the atmosphere increased 20% between 2010 and 2015, with South America, Sub-Saharan Africa and Southeast Asia as the main contributors. Approximately 80% of the total mercury emissions in South America is from the Amazon, where the presence of the metal is ubiquitous and highly dynamic. The presence of this metal is likely increasing, with global consequences, due to events of the last two years including extensive biomass burning and deforestation, as well as mining activities and the construction of large-scale projects, such as dams. Here we present a concise profile of this mobilization, highlighting the human exposure to this metal in areas without mining history. Mercury reaches the food chain in its most toxic form, methylmercury, intoxicating human populations through the intake of contaminated fish. Amazonian populations present levels over 6 ppm of hair mercury and, according to the 175:250:5:1 ratio for methylmercury intake : mercury hair : mercury brain : mercury blood, consume 2–6 times the internationally recognized reference doses. This exposure is alarmingly higher than that of other populations worldwide. A possible biphasic behavior of the mercury-related phenomena, with consequences that may not be observed in populations with lower levels, is hypothesized, supporting the need of improving our knowledge of this type of chronic exposure. It is urgent that we address this serious public health problem in the Amazon, especially considering that human exposure may be increasing in the near future. All actions in this region carry the potential to have global repercussions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Astrocytes represent heterogeneous in form and function population of cells responsible for homeostasis of the CNS.•Astroglial cradle modulates synaptic transmission through ...secretion of multiple signalling molecules.•Astrocyte-specific pathways regulate synaptogenesis, synaptic plasticity and synaptic elimination.•Astrocyte-specific molecular cascades contribute to learning, memory and cognition.•Astrocyte-specific mechanisms modify behaviours such as motor activity, mood, emotion, sleep, and food intake.
Astrocytes are a heterogeneous population of neural cells with diverse structural, functional and molecular characteristics responsible for homeostasis and protection of the central nervous system (CNS). Unlike neurones, astrocytes do not generate action potentials, but employ fluctuations of cytosolic ions as a substrate for their excitability. Ionic signals are associated with neuronal activity and these signals initiate an array of responses ranging from the activation of plasmalemmal homeostatic transporters to the secretion of numerous signalling molecules including neuromodulators, neurotransmitter precursors, metabolic substrates, trophic factors and cytokines. Thus, astrocytes regulate the synaptic connectivity of the neuronal networks by supporting neurotransmitter metabolism, synaptogenesis, synaptic elimination and the synaptic plasticity that contributes to cognitive processing including learning, memory, emotionality and behaviour. Astroglia-specific regulatory pathways affect the most fundamental properties of neuronal networks from their excitability to synaptic connectivity. Thus, it is the concerted action of glia and neurones, which, through distinct mechanisms, produce the behavioural outputs of the ultimate control centre that we call the brain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aim and Hypothesis
Here, we investigate the effect of SAD on physical and hemodynamic adaptations after long‐term treatment with Enalapril and concurrent exercise training (CET) in a model of ...menopause. We hypothesized that the beneficial effects of exercise training combined with antihypertensive drug therapy would be reduced after the chronic absence of arterial baroreceptor reflex.
Methods
Female spontaneously hypertensive rats (90 days old) were distributed (7‐8 animals/group) into ovariectomized groups: trained treated with E (OTE) and SAD trained treated with E (SAD‐OTE). SAD procedure was performed at initial of protocol. Ovariectomy consisted of bilateral removal of the ovaries. Enalapril (3mg/kg) was administrated orally in drinking water. CET (40‐60% maximal capacity) consisted of aerobic (motor treadmill) followed by resistance exercises (ladder adapted to rats), 3 days/wk for 8 weeks. Heart rate and BP variability were analyzed using signals of direct recording of BP. Vasopressor system was evaluated by sequential injection of a vasopressin receptor antagonist, losartan and hexamethonium.
Results
Treadmill performance was reduced in SAD group (p<0.001). There were no differences for systolic, diastolic, and mean blood pressure (BP) between groups. SAD increased resting heart rate (p<0.001). In addition, SAD‐OTE group showed lower variance of pulse interval (ms²) (49.2±22.5 vs. OTE: 96.5±49.6), as well as higher systolic BP variance (mmHg²) (84.1±36.9 vs. OTE: 34.2±9.0) and low‐frequency band (mmHg²) (11.2±4.9 vs. OTE: 6.5±3.4). BP reduction (mmHg) after vasopressin receptor antagonist (‐20.5±10.5) and hexamethonium (‐87.2±17.7) was higher in SAD‐OTE (vs. OTE: ‐6.9±4.6 and ‐56.0±10.4, respectively).
Conclusion
Despite similar BP control, drug therapy‐and training‐induced adaptations are blunted in absence of baroreceptor deafferentation, suggesting that this mechanism play a crucial role to maintain physical and cardiovascular autonomic benefits.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Organophosphate esters (OPEs) used as flame retardants and plasticizers are additives in building and construction materials, decorations, furniture, electronic equipment, among other applications. ...The presence of materials containing these substances in construction and demolition waste (CDW) from weak waste management practices can result in environmental contamination. In this study, OPEs’ presence in soil samples collected from a CDW landfill in Brazil was evaluated. Soil samples were collected in areas adjacent to CDW from an inert landfill, and the samples were analysed by gas chromatography coupled to mass spectrometry. The OPEs were detected in all soil samples at quantifiable concentrations ranging from 21 to 251 ng g−1, and detected compounds were tris(phenyl) phosphate, tris(2-butoxyethyl) phosphate, tris(1,3-dichloroisopropyl) phosphate, tris(2-chloroisopropyl) phosphate and 2-ethylhexyl diphenyl phosphate. The presence of these compounds in a CDW landfill is probably due to the lack of control of the materials sent to and deposited in the landfill, which, results in part from the lack of sampling and screening systems that can help identify the presence of contaminants in the CDW waste stream. This is partially due to OPEs not being considered controlled compounds under current regulations, thus screening or separation for handling of OPEs at construction and demolition work sites is rare to non-existent. The data generated in this study reveals the need for improving CDW management to minimize, if not eliminate, environmental contamination by OPEs.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
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•Unzipping process increased capacitance in 32% by improving electroactive area.•Hydrogen plasma allowed to synthesize single layer graphene sheets from CNTs.•MWCVD emerged as a ...controllable process to modify carbon nanotubes structure.
Carbon nanotubes (CNTs) are well known by their unique properties, such as high electrical conductivity and chemical stability, which can improve charge transfer, facilitating double layer charging in supercapacitor devices. In this work we report on a simple method to unzip CNTs, producing graphene sheets. The amount of hydrogen atoms in the nanotubes synthesis by micro-wave chemical vapor deposition is a critical parameter for unzipping process. High crystalline quality graphene sheets are obtained by this method because of the sp2 bonds sensibility to hydrogen ions reactivity. Unzipped CNTs provided higher capacitance values without an increase in pseudocapacitance. The resulting structure presented an increase in double-layer charging, suggesting a material with good electron transfer rate. This new synthesis method is promising for obtainment of graphene sheets from carbon nanotubes. Besides, unzipped carbon nanotubes presented themselves to be a good alternative for supercapacitors electrodes material.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Human exposure to mercury is a major public health concern, causing neurological outcomes such as motor and visual impairment and learning disabilities. Currently, human exposure in the Amazon is ...among the highest in the world. A recent systematic review (doi:10.1016/j.jtemb.2018.12.001), however, highlighted the lack of high-quality studies on mercury-associated neurotoxicity. There is, therefore, a need to improve research and much to still learn about how exposure correlates with disease. In this review, we discuss studies evaluating the associations between neurological disturbances and mercury body burden in Amazonian populations, to generate recommendations for future studies. A systematic search was performed during July 2020, in Pubmed/Medline, SCOPUS and SCIELO databases with the terms (mercury*) and (Amazon*). Four inclusion criteria were used: original article (1), with Amazonian populations (2), quantifying exposure (mercury levels) (3), and evaluating neurological outcomes (4). The extracted data included characteristics (as year or origin of authorship) and details of the research (as locations and type of participants or mercury levels and neurological assessments). Thirty-four studies, most concentrated within three main river basins (Tapajós, Tocantins, and Madeira) and related to environmental exposure, were found. Mercury body burden was two to ten times higher than recommended and main neurological findings were cognitive, vision, motor, somatosensory and emotional deficits. Important insights are described that support novel approaches to researching mercury exposure and intoxication, as well as prevention and intervention strategies. As a signatory country to the Minamata Convention, Brazil has the opportunity to play a central role in improving human health and leading the research on mercury intoxication.
•Exposure to mercury in Amazonian population (AP) is among the highest in the world.•Knowledge on neurological changes in exposed vulnerable populations has to improve.•Measurements over time and the exact context of exposure are among recommendations.•Neurological tests are recommended to appropriately define the neurological effects.•AP in the Negro Basin has high mercury with unknown neurological consequences.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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