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1.
Plants (Basel) ; 12(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37111835

RESUMO

Rice (Oryza sativa L.) is one of the most economically and socially important cereals in the world. Several strategies such as biofortification have been developed in a way eco-friendly and sustainable to enhance crop productivity. This study implemented an agronomic itinerary in Ariete and Ceres rice varieties in experimental fields using the foliar application of selenium (Se) to increase rice nutritional value. At strategic phases of the plant's development (at the end of booting, anthesis, and at the milky grain stage), they were sprayed with sodium selenate (Na2SeO4) and sodium selenite (Na2SeO3). In the first foliar application plants were sprayed with 500 g Se·ha-1 and in the remaining two foliar applications were sprayed with 300 g Se·ha-1. The effects of Se in the level of micro and macronutrients in brown grains, the localization of Se in these grains, and the subsequent quality parameters such as colorimetric characteristics and total protein were considered. After grain harvesting, the application of selenite showed the highest enrichment in all grain with levels reaching 17.06 µg g-1 Se and 14.28 µg g-1 Se in Ariete and Ceres varieties, respectively. In the Ceres and Ariete varieties, biofortification significantly affected the K and P contents. Regarding Ca, a clear trend prevailed suggesting that Se antagonizes the uptake of it, while for the remaining elements in general (except Mn) no significant differences were noted. Protein content increased with selenite treatment in the Ariete variety but not in Ceres. Therefore, it was possible to conclude, without compromising quality, that there was an increase in the nutritional content of Se in brown rice grain.

2.
Int J Mol Sci ; 24(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36982644

RESUMO

Kα,ß X-ray lines from photon excitation were measured in selected elements from Mg to Cu using a high-resolution double-crystal X-ray spectrometer with a proportional counter, and the Kß/Kα intensity ratio for each element was obtained, after correcting for self-absorption, detection efficiency, and crystal reflectance. This intensity ratio increases rapidly from Mg to Ca but, in the 3d elements region, the increase becomes slower. This is related to the intensity of the Kß line involving valence electrons. The slow increase of this ratio in the 3d elements region is thought to be due to the correlation between 3d and 4s electrons. Moreover, the chemical shifts, FWHM, asymmetry indices, and Kß/Kα intensity ratios of the Cr compounds, due to different valences, were also investigated using the same double-crystal X-ray spectrometer. The chemical effects were clearly observed, and the Kß/Kα intensity ratio was found to be compound-dependent for Cr.


Assuntos
Elétrons , Raios X
3.
Plants (Basel) ; 11(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36145843

RESUMO

Nowadays, there is a growing concern about micronutrient deficits in food products, with agronomic biofortification being considered a mitigation strategy. In this context, as Zn is essential for growth and maintenance of human health, a workflow for the biofortification of grapes from the Vitis vinifera variety Fernão Pires, which contains this nutrient, was carried out considering the soil properties of the vineyard. Additionally, Zn accumulation in the tissues of the grapes and the implications for some quality parameters and on winemaking were assessed. Vines were sprayed three times with ZnO and ZnSO4 at concentrations of 150, 450, and 900 g ha-1 during the production cycle. Physiological data were obtained through chlorophyll a fluorescence data, to access the potential symptoms of toxicity. At harvest, treated grapes revealed significant increases of Zn concentration relative to the control, being more pronounced for ZnO and ZnSO4 in the skin and seeds, respectively. After winemaking, an increase was also found regarding the control (i.e., 1.59-fold with ZnSO4-450 g ha-1). The contents of the sugars and fatty acids, as well as the colorimetric analyses, were also assessed, but significant variations were not found among treatments. In general, Zn biofortification increased with ZnO and ZnSO4, without significantly affecting the physicochemical characteristics of grapes.

4.
Plants (Basel) ; 11(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35890488

RESUMO

As the productivity and quality of tomato fruits are responsive to Mg applications, without surpassing the threshold of toxicity, the assessment of potential levels of Mg accumulation in tissues, as well as the interactions with Ca and physicochemical properties, prompt this study. An agronomic workflow for Mg enrichment, consisting of six foliar applications of MgSO4 with four concentrations (0%, 0.25%, 1% and 4%), equivalent to 0, 43.9, 175.5 and 702 g ha-1, was applied on two tomato (Lycopersicum esculentum L.) genotypes (Heinz1534 and Heinz9205). During fruit development, leaf gas exchange was screened, with only minor physiological deviations being found. At harvest, Mg contents among tissues and the interactions with Ca were analyzed, and it was found that in both varieties a higher Mg/Ca ratio prevailed in the most external part of the fruit sprayed with 4% MgSO4. However, Mg distribution prevailed relatively near the epidermis in H1534, while in H9205 the higher contents of this nutrient occurred in the core of the fruit, which indicated a decrease of the relative proportion of Ca. The morphologic (height and diameter), physical (dry weight and density) and colorimetric parameters, and the total soluble solids of fruits, did not reveal significant changes in both tomato varieties. It was further concluded that foliar application until 4% MgSO4 does not have physiological impacts in the fruit's quality of both varieties, but in spite of the different patterns of Mg accumulation in tissues, if the mean value in the whole fruit is considered, this nutrient prevails in H1534. This study thus suggests that variety H1534 can be used to attain tomato fruits with added value, providing an option of further processing to achieve food products with functional properties, ultimately proving a beneficial option to producers, the food processing industry and consumers. Moreover, the study reinforces the importance of variety choice when designing enrichment workflows.

5.
Plants (Basel) ; 11(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35807677

RESUMO

Calcium is essential for plants, yet as its mobility is limited, the understanding of the rate of Ca2+ accumulation and deposition in tissues of tubers, as well as the interactions with other critical nutrients prompted this study. To assess the interactions and differential accumulation of micro and macronutrients in the tissues of tubers, Solanum tuberosum L. varieties Agria and Rossi were cultivated and, after the beginning of tuberization, four foliar sprayings (at 8-10 day intervals) with CaCl2 (3 and 6 kg ha-1) or Ca(NO3)2 (2 and 4 kg ha-1) solutions were performed. It was found that both fertilizers increased Ca accumulation in tubers (mostly in the parenchyma tissues located in the center of the equatorial region). The functioning of the photosynthetic apparatus was not affected until the 3rd application but was somewhat affected when approaching the end of the crop cycle (after the 4th application), although the lower dose of CaCl2 seemed to improve the photochemical use of energy, particularly when compared with the greater dose of Ca(NO3)2. Still, none of these impacts modified tuber height and diameter. Following the increased accumulation of Ca, in the tubers of both varieties, the mean contents of P, K, Na, Fe, and Zn revealed different accumulation patterns. Moreover, accumulation of K, Fe, Mn, and Zn prevailed in the epidermis, displaying a contrasting pattern relative to Ca. Therefore, Ca accumulation revealed a heterogeneous trend in the different regions analyzed, and Ca enrichment of tubers altered the accumulation of other nutrients.

6.
Plants (Basel) ; 11(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35684172

RESUMO

Grapes and wine are widely consumed in the world, yet their mineral content can be influenced by many factors such as the mineral composition of soils, viticulture practices and environmental conditions. In this context, considering the importance of Zn in the human physiology, the enrichment of Moscatel and Castelão grapes (white and red variety, respectively) with this nutrient prompted this study; further assessment of tissue deposition and some implications for wine production. Using two foliar fertilizers (ZnO or ZnSO4, at 150, 450 and 900 g ha-1), decreases in net photosynthesis and stomatal conductance occurred in both varieties, suggesting that the physiological threshold of Zn toxicity was reached without visible symptoms. Following foliar spraying with both fertilizers, the content of Zn in leaves of the Castelão and Moscatel varieties showed higher values in all treatments relative to the control. Moreover, in grapes this tendency occurred only in Castelão. Concerning Cu, Fe, Ca, K, S and P, some significant differences also happened in leaves and grapes among treatments. At harvest, the indexes of Zn enrichment in grapes increased between 2.14- and 8.38-fold and between 1.02- and 1.44-fold in Castelão and Moscatel varieties, respectively. Zinc in the dried skin of Castelão only increased with ZnO and ZnSO4 sprayed at 900 g ha-1 (ca. 2.71- and 1.5-fold relative to the control, respectively), but in Moscatel a clear accumulation trend could not be found. The dry weight of grapes ranged (in %) between 16 and 23 (but did not vary significantly among treatments of each variety or in each treatment between varieties), and total soluble solids (e.g., mainly soluble sugars and proteins) and color parameters showed some significant variations. Through winemaking, the contents of Zn increased in both varieties (1.34- and 3.57-fold, in Castelão and Moscatel, respectively) and in all treatments, although non-significantly in Castelão. It is concluded that, to increase the contents of Zn in grapes without reaching the threshold of toxicity, ZnO or ZnSO4 can be used for foliar spraying of Castelão and Moscatel varieties until 900 g ha-1 and that winemaking augments the level of this nutrient.

7.
Sci Rep ; 12(1): 1864, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115617

RESUMO

This study aimed to verify the effects of congested fixture and matches' participation on internal and external workload indexes in professional Brazilian soccer players. Rate of perceived exertion-based training load (sRPE), distance- and accelerometry-based measures were daily monitored over 119 training sessions and 33 matches performed by 29 male outfield players. Weeks were classified as congested (n = 11, two or more matches within a 7-day period) and regular (n = 10, one match or less within a 7-day period). The players were divided based on the matches' participation: (1) players who played ≥ 60 min (G1); (2) players who played < 60 min (G2); (3) players who did not participate of the match (G3). The findings showed that independent of the levels of participation during the matches, regular weeks presented greater acute, monotony, and strain indices for internal and external workload measures than congested weeks. The G1 presented the highest values for most of the workload indices in both regular and congested weeks, except for monotony indices (internal and external load) that G2 showed greater values than G1 and G3. Coaches and practitioners should plan the training "doses" to reduce disparities of these different match's participation and congested schedule weeks.


Assuntos
Atletas , Comportamento Competitivo , Condicionamento Físico Humano , Futebol , Carga de Trabalho , Acelerometria , Adulto , Brasil , Humanos , Masculino , Esforço Físico , Fatores de Tempo , Adulto Jovem
8.
J Strength Cond Res ; 36(6): 1643-1647, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32639381

RESUMO

ABSTRACT: Guerra, MA Jr, Caldas, LA, Souza, HL, Tallis, J, Duncan, MJ, and Guimarães-Ferreira, L. The effects of physical fitness on postactivation potentiation in professional soccer athletes. J Strength Cond Res 36(6): 1643-1647, 2022-To investigate the relationship of the response to postactivation potentiation (PAP) with scores of physical fitness. Twenty-four professional male soccer players undertook tests of agility, muscular power, aerobic capacity, and body composition. Conditioning activities (CAs) were performed consisting of plyometrics exercises and sprints with sled towing. In the first and second sessions, body composition, agility, power, and aerobic capacity were assessed. At the third session, countermovement jumps (CMJ) were performed with 1, 3, and 5 minutes after the execution of the CA. Significant differences were found for CMJ height 1, 3, and 5 minutes after the CA compared with baseline values (3.58, 5.10, 5.48%, respectively). There was a significant positive correlation between the level of general physical fitness and PAP (CMJ height increase) 5 minutes after (r = 0.73). When the athletes were divided into groups with higher and lower physical fitness, the CA caused a significant increase in CMJ height in both groups, but a significant difference (p < 0.05) was observed at all times after PAP induction, with better performance in higher versus lower fitness level. The results suggest that plyometrics exercises associated with sled towing sprints as a CA result in an increase in CMJ performance in athletes and that physical fitness directly influences the PAP occurrence, with higher fit players demonstrating an enhanced PAP response.


Assuntos
Desempenho Atlético , Aptidão Física , Futebol , Atletas , Desempenho Atlético/fisiologia , Humanos , Masculino , Força Muscular/fisiologia , Aptidão Física/fisiologia , Futebol/fisiologia
9.
J Trace Elem Med Biol ; 69: 126874, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34700157

RESUMO

BACKGROUND: Mercury (Hg) is a globally ubiquitous pollutant and one of the most dangerous metal contaminants, which presents a high risk of bioaccumulation in living organisms. In this study, we mapped the distribution of Hg and other trace elements in zebrafish (Danio rerio), which were exposed to mercury (II) chloride in order to assess its toxicity, bioaccumulation and distribution in fish organs. METHODS: Adult zebrafish were exposed for 7 days to different concentrations of mercury (II) chloride and the elemental distribution was obtained through the micro-energy dispersive X-ray fluorescence technique (µ-EDXRF). RESULTS: The results showed that Hg levels, measured in fish tissues, were indicative of bioaccumulation within some of its organs (e.g. visceral mass, gills), and that the physiological processes of accumulation were highly dose-dependent. In addition, the results showed higher concentrations of Hg in the gills. Moreover, other trace elements (e.g. Fe, Cu and Zn) levels were not altered after fish exposure to mercury(II) chloride. CONCLUSION: The µ-EDXRF results were assessed along with the determination of some oxidative stress biomarkers (e.g. antioxidant enzymes) to understand the effects behind the Hg bioaccumulation and toxicity. These results suggest that the metabolic changes in zebrafish due to the exposure to Hg are consistent with oxidative stress.


Assuntos
Mercúrio , Oligoelementos , Poluentes Químicos da Água , Animais , Cloretos/toxicidade , Fluorescência , Mercúrio/análise , Mercúrio/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Raios X , Peixe-Zebra
10.
Plants (Basel) ; 10(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34685850

RESUMO

The aim of this study is to evaluate the elemental composition of fifteen algae-based supplements commonly sold in the Portuguese market, by energy dispersive X-ray fluorescence. Despite the fact that the majority of Kelp samples were a good source of iodine, the levels observed might well contribute to an excess in the human body, which can cause dysfunction of the thyroid gland. Furthermore, the presence of lead in Sea spaghetti, Arame, Hijiki and Wakame caused a considerable risk to public health vis a vis possible ingestion of a high daily dose. Regarding arsenic, great variability was observed in all the samples with concentrations equal to or above 60 µg/g in the case of Arame, KelpJ and Hijiki. Although algae mainly accumulate organic arsenic, some also contain high levels of its inorganic form, as is commonly pointed out for Hijiki. Thus, regular ingestion of these supplements must also take into account the mentioned facts. There is no doubt that these supplements are also good sources of other nutrients, but the lack of accurate regulations and control should alert consumers to avoid indiscriminate use of these types of products.

11.
Plants (Basel) ; 10(4)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806210

RESUMO

The contamination of abandoned mining areas is a problem worldwide that needs urgent attention. Phytoremediation emerges as a successful method to extract different contaminants from the soil. In this context, Eucalyptus globulus plants growing in soils artificial contaminated with arsenic (As) were used to access its phytoremediation capabilities. The effects of As on photosynthetic performance were monitored through different physiological parameters, whereas the uptake and translocation of As and the putative effects on calcium, iron, potassium, and zinc levels on plants were evaluated by X-ray fluorescence analysis. Root system is the major accumulator organ, while the translocation to the above-ground organs is poor. In the end of the experiment, the root biomass of plants treated with 200 µg As mL-1 is 27% and 49.7% lower than equivalent biomass from plants treated with 100 µg As mL-1 and control plants, respectively. Each plant can accumulate 8.19 and 8.91 mg As after a 6-month period, when submitted to 100 As and 200 As, respectively. It seems to exist an antagonistic effect of As on Zn root uptake by E. globulus. In general, the tested concentrations do not influence negatively plant metabolism, indicating that this species is suitable for plantation in contaminated areas.

12.
Plants (Basel) ; 10(2)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546440

RESUMO

An agronomic itinerary for Se biofortification of two rice cultivars (Ariete and Ceres) through foliar fertilization with sodium selenate and sodium selenite with different concentrations (25, 50, 75 and 100 g Se.ha-1), was implemented in experimental fields. The selenium toxicity threshold was not exceeded, as shown by the eco-physiological data obtained through leaf gas exchanges. The highest Se enrichment in paddy grains was obtained with selenite for both cultivars, especially at the highest doses, i.e., 75 and 100 g Se.ha-1, with approximately a 5.0-fold increase compared with control values. In paddy grains, Zn was the most affected element by the treatments with Se with decreases up to 54%. When comparing the losses between rough and polished grains regardless of the cultivars, Se species and concentrations, it was observed that only Cu, Mg and Zn exhibited losses <50%. The remaining elements generally had losses >70%. The loss of Se is more pronounced in Ceres cultivar than in Ariete but rarely exceeds 50%. The analysis by µ-EDXRF showed that, in Ariete cultivar, Se is mostly homogeneously distributed in the grain regardless of any treatments, while in Ceres cultivar, the Se distribution seems to favor accumulation in the periphery, perhaps in the bran.

13.
Plants (Basel) ; 10(2)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494526

RESUMO

This study aimed to assess the implications of Zn enrichment in wheat grains as a function of contrasting genotypes, edaphic conditions and foliar fertilizers. Triticum aestivum L. varieties Roxo and Paiva were grown in four production fields, and sprayed with ZnSO4 (0, 16.20 and 36.40 kg/ha) Zn-EDTA (0, 6.30 and 12.60 kg/ha) and Tecnifol Zinc (0, 3.90 and 7.80 kg/ha). The heterogeneous edaphic conditions of the wheat fields were chemically characterized, it being found that soil properties determine different Zn accumulation in the grains of both genotypes. Foliar spraying enhanced to different extents Zn content in the grains of both genotypes, but the average of enrichment indexes varied among the wheat fields. Zinc mostly accumulated in the embryo and vascular bundle and to a lesser extent in the endosperm. Grain yield and test weight sprayed by ZnSO4 gave the highest values in both genotypes, but the opposite was found for Zn-EDTA. Considering the color parameters, lightness and red-green transitions were found to be a conjunction of genotype characteristics, fertilization types and edaphic conditions prevailing in each field. It is concluded that the index of Zn enrichment in wheat grains is a docket of edaphic conditions, genotype and type of fertilization.

14.
Plants (Basel) ; 10(2)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513848

RESUMO

This study aimed to assess the efficiency of Ca enrichment in tubers of three genotypes of Solanum tuberosum L., through foliar spraying with CaCl2 and Ca(NO3)2 solutions. In this context, soil heterogeneity of three potato-growing fields, as well as the implications of Ca accumulation among tissues and some quality parameters were assessed. Three potato varieties (Agria, Picasso and Rossi) were grown in three production fields and during the life cycle, four pulverizations with calcium chloride (3 and 6 kg ha-1) or calcium nitrate (0.5, 2 and 4 kg ha-1) were applied. For screening the potential phytotoxicity, using Agria as a test system, the potential synthesis of photoassimilates was determined, and it was found that after the 3rd Ca application, leaf gas exchanges were moderately (net photosynthesis), to strongly (stomatal conductance) affected, although without impact on Ca accumulation in tubers. At harvest, the average Ca biofortification index varied between 5-40%, 40-35% and 4.3-13% in Agria, Picasso and Rossi, respectively. Moreover, the equatorial region of the tubers in general showed that Ca accumulation prevailed in the epidermis and, in some cases, in inner areas of the potato tubers. Biofortified tubers with Ca also showed some significant changes in total soluble solids and colorimetric parameters. It is concluded that Ca enrichment of potato tubers through foliar spraying complemented the xylem mass flow of Ca from roots, through phloem redistribution. Both fertilizers showed similar efficiency, but Rossi revealed a lower index of Ca accumulation, eventually due to different metabolic characteristics. Although affected by Ca enrichment, potato tubers maintained a high quality for industrial processing.

15.
RSC Adv ; 11(42): 26344-26353, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35479447

RESUMO

The use of nanomaterials to improve medical diagnostics and therapeutics has been rapidly increasing. Among these materials are gold nanoparticles, which can be functionalized to target specific cells, acting as nanovectors for drug delivery, enhanced contrast agents as well as other targeted therapies. Au nanoparticles are very useful as they selectively accumulate in tumour sites due to the enhanced permeability-retention effect. There is however little information about the spatial distribution of the nanoparticles within tumours, which might hinder efficient therapies. In this study, X-ray fluorescence was used to investigate the diffusion of gold nanoparticles in cancer cell spheroids mimicking true tumour growth. Functionalization of the nanoparticles has the effect of allowing better diffusion into and out of the spheroid, while those nanoparticles that are only partially covered rapidly formed aggregates. This clustering led to size exclusion during transport within the tumour, changing its distribution profile while greatly increasing the nanoparticle concentration.

16.
Plants (Basel) ; 9(12)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260543

RESUMO

In worldwide production, rice is the second-most-grown crop. It is considered a staple food for many populations and, if naturally enriched in Se, has a huge potential to reduce nutrient deficiencies in foodstuff for human consumption. This study aimed to develop an agronomic itinerary for Se biofortification of Oryza sativa L. (Poaceae) and assess potential physicochemical deviations. Trials were implemented in rice paddy field with known soil and water characteristics and two genotypes resulting from genetic breeding (OP1505 and OP1509) were selected for evaluation. Plants were sprayed at booting, anthesis and milky grain phases with two different foliar fertilizers (sodium selenate and sodium selenite) at different concentrations (25, 50, 75 and 100 g Se·ha-1). After grain harvesting, the application of selenate showed 4.9-7.1 fold increases, whereas selenite increased 5.9-8.4-fold in OP1509 and OP1505, respectively. In brown grain, it was found that in the highest treatment selenate or selenite triggered much higher Se accumulation in OP1505 relatively to OP1509, and that no relevant variation was found with selenate or selenite spraying in each genotype. Total protein increased exponentially in OP1505 genotype when selenite was applied, and higher dosage of Se also increased grain weight and total protein content. It was concluded that, through agronomic biofortification, rice grain can be enriched with Se without impairing its quality, thus highlighting its value in general for the industry and consumers with special needs.

17.
Plants (Basel) ; 9(7)2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32650463

RESUMO

The increasing demand of organic agriculture (OA) is based on the consumer's belief that organic agricultural products are healthier, tastier and more nutritious. The effect of OA and conventional agriculture (CA) methods on the elemental compositions of green and red sweet peppers were studied. The highest concentrations of Ca, Cu, K and P occur in peppers from OA in both states of ripeness, with emphasis on Ca and K contents. Furthermore, the principal component analysis (PCA), points out to a clear separation, regarding concentrations, between peppers from OA and CA. The average fruit weight is higher in OA, 141 g versus 112 g in CA. Regarding productivity, CA reaches a value of 30.1 t/ha, 7% higher than the value observed for OA, i.e., 28 t/ha. Peppers from CA, exhibited greater protein content than those which originated from OA, regardless of the ripening stage, but not more ashes. Regarding nutritional ratios, the ripening stage and the production mode, can be important for an adequate choice regarding a more balanced Ca/P ratio, and the studied variety contained high Ca values ranging between 1009 and 1930 mg.kg-1. The PCA analysis also revealed that Mn and Fe are inversely correlated, confirming the importance of the Mn/Fe ratio evaluation in nutritional studies.

18.
Nutrients ; 11(6)2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31242545

RESUMO

Mixed martial arts (MMA) is a combat sport where competitors utilize strikes (punches, kicks, knees, and elbows) and submission techniques to defeat opponents in a cage or ring. The aim of this study was to investigate the effect of acute caffeine ingestion on punching performance by professional MMA athletes. The study used a double-blind, counterbalanced, crossover design. Eleven professional MMA competitors (27.6 ± 4.3 years and 83.5 ± 7.8 kg of body weight) ingested a dose of caffeine (5 mg·kg-1) or placebo 60 min prior to three sets of punching. Each set consisted of 15 s, at which participants were asked to perform straight punches with maximum strength and frequency with his dominant arm. After each set, a 45 s recovery time was applied. Using a force transducer attached to a cushioned plate, the punch frequency, and mean and maximal punch force was measured. The readiness to invest in both physical (RTIPE) and mental (RTIME) effort was assessed prior to the protocol, and the rating of perceived exertion (RPE) was recorded after. Caffeine ingestion did not result in increased punching frequency, mean and maximum punch force, RTIPE, RTIME, and RPE when compared to the placebo condition. Based on these results, acute caffeine ingestion did not improve punching performance in professional MMA athletes.


Assuntos
Atletas , Desempenho Atlético , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Artes Marciais , Adulto , Brasil , Estudos Cross-Over , Método Duplo-Cego , Nível de Saúde , Humanos , Masculino , Força Muscular , Fatores de Tempo , Adulto Jovem
19.
Biol Trace Elem Res ; 187(2): 596-601, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948912

RESUMO

Synchrotron radiation X-ray fluorescence spectroscopy, in conjunction with atomic absorption and Raman spectroscopy, was used to analyze a set of top brand tattoo inks to investigate the presence of toxic elements and hazardous substances. The Cr, Cu, and Pb contents were found to be above the maximum allowed levels established by the Council of Europe through the resolution ResAP(2008)1 on requirements and criteria for the safety of tattoos and permanent makeup. Raman analysis has revealed the presence of a set of prohibited substances mentioned in ResAP(2008)1, among which are the pigments Blue 15, Green 7, and Violet 23. Other pigments that were identified in white, black, red, and yellow inks are the Pigment White 6, Carbon Black, Pigment Red 8, and a diazo yellow, respectively. The present results show the importance of regulating tattoo ink composition.


Assuntos
Substâncias Perigosas/análise , Tinta , Metais/análise , Análise Espectral/métodos , Tatuagem , Cádmio/análise , Cromo/análise , Cobre/análise , Humanos , Chumbo/análise , Mercúrio/análise , Níquel/análise , Espectrometria por Raios X/métodos , Espectrofotometria Atômica/métodos , Análise Espectral Raman/métodos
20.
Environ Sci Pollut Res Int ; 26(3): 2512-2522, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30471064

RESUMO

Soils and different vegetable species in Costa de Caparica (Portugal) are subject to the intensive use of inorganic fertilizers and pesticides. Thus, the concentrations of As, Cu, Fe, Mn, Pb, and Zn were evaluated. Lettuce, spinach, and potatoes collected in station 9 cause reason for concern due to their high Pb concentrations close to 20 µg g-1 which is probably related to an intensive use of copper and iron sulphate fertilizers. Additionally, the consumption of Portulaca oleracea collected in stations 3 and 4 must be avoided due to the high concentrations of Zn, and even Cu. The derived estimated daily intake (EDI) dose of Zn will be a risk to human consumption if P. oleracea was the single basis of a soup, although the addition of other ingredients might lower the tolerable upper intake (TUI) value of 39 mg/day of P. oleracea, to admissible levels, i.e., not exceeding 25 mg/day. Pumpkin collected in station 1 contained 44.1 µg g-1 Cu and a TUI value of 9.8 mg/day, when the recommendation must not exceed 5.0 mg/day. In this context, it is strongly advised to not include this vegetable in household menus.


Assuntos
Produtos Agrícolas/química , Fertilizantes/análise , Metais Pesados/análise , Praguicidas/análise , Poluentes do Solo/análise , Solo/química , Monitoramento Ambiental , Humanos , Portugal , Verduras/química
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