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1.
Br J Nutr ; : 1-6, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39465578

RESUMEN

This article aims to evaluate the sociodemographic determinants of ultra-processed foods (UPF) consumption in the Brazilian population ≥ 10 years of age. The study used data from the personal and resident food consumption module of the Family Budget Surveys, grouping foods according to the NOVA classification of food processing. The classification and regression tree (CART) was used to identify the factors determining the lowest to highest percentage participation of UPF in the Brazilian population. UPF accounted for 37·0 % of energy content in 2017-2018. In the end, eight nodes of UPF consumption were identified, with household situation, education in years, age in years and per capita family income being the determining factors identified in the CART. The lowest consumption of UPF occurred among individuals living in rural areas with less than 4 years of education (23·78 %), while the highest consumption occurred among individuals living in urban areas, < 30 years of age and with per capita income ≥ US$257 (46·27 %). The determining factors identified in CART expose the diverse pattern of UPF consumption in the Brazilian population, especially conditions directly associated with access to these products, such as penetration in urban/rural regions. Through the results of this study, it may be possible to identify focal points for action in policies and actions to mitigate UPF consumption.

2.
Eur Ann Allergy Clin Immunol ; 55(4): 180-188, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35261226

RESUMEN

Summary: Background. Patients and Public Involvement in every stage of the patient-centered health research cycle is the key to the development of innovative solutions with an impact on patients' care. Methods. This protocol describes the development of ConectAR, a network to promote the involvement of patients with asthma and their carers in the health research cycle. Results. This protocol comprehends 4 tasks: 1) define the mission, vision, governance and activities of the network through focus groups; 2) establish the communication strategy and tools; 3) test the feasibility of the network in a Delphi study on the research priorities for asthma in Portugal; 4) coordination and dissemination activities. Conclusions. This network will improve research by ensuring that patients and carers have an active role in the co-creation of impactful solutions for asthma.


Asunto(s)
Asma , Cuidadores , Humanos , Grupos Focales , Portugal
3.
Lett Appl Microbiol ; 74(6): 863-872, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35148433

RESUMEN

Flow cytometry has emerged as a promising technique for detection of SARS-CoV-2 antibodies. In this study, we developed an innovative strategy for simultaneous detection of immunoglobulin G (IgG), IgM and IgA. The SARS-CoV-2 nucleocapsid protein was covalently bound to functional beads surface applying sulpho-SMCC chemistry. BUV395 anti-IgG, BB515 anti-IgM, biotinylated anti-IgA1/IgA2 and BV421 streptavidin were used as fluorophore conjugated secondary antibodies. Serum and antibodies reaction conditions were optimized for each antibody isotype detection and a multiplexed detection assay was developed. This new cell-free assay efficiently discriminate COVID-19 negative and positive samples. The simultaneous detection of IgG, IgM and IgA showed a sensitivity of 88·5-96·2% and specificity of 100%. This novel strategy opens a new avenue for flow cytometry-based diagnosis.


Asunto(s)
Anticuerpos Antivirales , COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales/sangre , COVID-19/diagnóstico , Citometría de Flujo , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Proteínas de la Nucleocápside , SARS-CoV-2/inmunología , Sensibilidad y Especificidad
4.
Reumatismo ; 72(4): 197-206, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33677946

RESUMEN

Limb vascular claudication and hand muscle weakness are common symptoms of Takayasu arteritis (TAK). However, no studies have correlated these two symptoms. Therefore, the aim of the study was to evaluate handgrip strength and its correlation with both upper-limb vascular claudication and imaging of the vessels. This cross-sectional study compared 36 patients with TAK who were matched by age, gender, and body mass index with 36 individuals without TAK (CTR). Hand strength (assessed with handgrip dynamometer), functional capacity (Health Assessment Questionnaire, HAQ), upper-limb vascular claudication symptoms (patients' selfreported form), and disease activity (Indian Takayasu Clinical Activity Score [ITAS] 2010; Physician Global Assessment [PGA], C-reactive protein, and erythrocyte sedimentation rate) were evaluated as well as vessel imaging (e.g., angiotomography or angioresonance) and blood pressure. The median age of the patients was 42.0 years (35.5-51.5 years), whereas the mean disease duration was 13.1±6.8 years. No patient had active disease. Compared to the CTR, the patients with TAK showed reduced strength in the left-hand (22.9±5.9 vs 26.3±5.6 kg; p=0.014) and increased HAQ scores [0.50 (0.12-0.87) vs 0.00 (0.00-0.00); p<0.001]. Both groups had comparable blood pressure. Among patients with TAK, lefthand strength was inversely correlated with HAQ (Spearman correlation: rho=-0.584; p<0.001) and positively correlated with right-hand strength (rho=0.644; p<0.001). Moreover, neither hand's strengths in the patients were correlated with subclavian stenosis imaging, blood pressure or limb vascular claudication. The reduction of strength in the upper left limb is inversely related to the functional capacity (HAQ score) of TAK. This reduction appears unrelated to classical vascular claudication, vessel imaging or blood pressure.


Asunto(s)
Arteritis de Takayasu , Adulto , Sedimentación Sanguínea , Estudios Transversales , Fuerza de la Mano , Humanos , Arteritis de Takayasu/complicaciones , Arteritis de Takayasu/diagnóstico por imagen , Extremidad Superior
6.
Reumatismo ; 72(2): 103-110, 2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32700876

RESUMEN

Vessel imaging in Takayasu arteritis (TAK) is often performed in clinical practice following laboratory test abnormalities or clinical symptoms, such as limb claudication. Conversely, the association between limb claudication and vessel imaging manifestations has not been assessed. This observational, cross-sectional study analyzed 139 adult TAK patients from 2000 to 2018. Their arterial vessel imaging information (especially significant stenosis and occlusion data) was registered and crosschecked with clinical and laboratory data. When vessel imaging was performed, the median age and disease duration of the patients were 38 (27.3-47.0) and 5.0 (1.0-12.0) years, respectively. There was no association between arterial abnormalities and demographic data, constitutional symptoms or laboratory parameters. Limb claudication was reported in 42 patients (30.2%): 17.3% reported it in the upper left limb (ULL), 12.2% reported it in the upper right limb (URL), 12.9% reported it in the lower left limb (LLL), and 12.2% reported it in the lower right limb (LRL). When crossmatched with imaging, both ULL and URL were associated with left vertebral artery stenosis/occlusion, and URL was associated with right iliac artery stenosis/occlusion, but no other association was found. In contrast, both LLL and LRL claudication were associated with infrarenal aortic, left iliac and right iliac artery stenosis/ occlusion (p<0.05). Moreover, the ULL and URL claudication symptoms were significantly associated with each other (p<0.001). Upper limb claudication was associated only with left vertebral artery stenosis/occlusion, whereas the subclavian arteries were not, suggesting that the symptom might not be fully explained by limb ischemia. In contrast, lower limb claudication was associated especially with infrarenal aortic and/or iliac arteries stenosis/occlusion.


Asunto(s)
Angiografía , Extremidades/irrigación sanguínea , Claudicación Intermitente/diagnóstico , Claudicación Intermitente/etiología , Arteritis de Takayasu/complicaciones , Arteritis de Takayasu/diagnóstico por imagen , Adulto , Estudios Transversales , Autoevaluación Diagnóstica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos
7.
Allergol Immunopathol (Madr) ; 46(2): 167-174, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29366523

RESUMEN

BACKGROUND: Although it is well known that allergic diseases involve a strong Th2 immune response, with production of high levels of specific IgE allergen, knowledge on the association between filarial infection and allergies, among paediatric patients is scarce. OBJECTIVE: To evaluate the allergic response patterns in cases of filarial infection by comparing peripheral eosinophils, total IgE levels, immediate hypersensitivity and cytokine levels in children and adolescents in Brazil. METHODS: This was an exploratory study with three groups: (I) with filarial infection and without allergic diseases; (II) without filarial infection and with allergic diseases; and (III) without filarial infection and without allergic diseases. The prick test and specific IgE tests for aeroallergens were performed using five antigens. Peripheral eosinophils and total IgE were also evaluated. IL-4 and IL-5 were determined using whole-blood culture stimulated by three antigens. RESULTS: Eosinophilia and elevated levels of total IgE (≥400IU/dl) were observed in all groups. The prick test was positive in 56.6% of the cases. Group I presented hypersensitive responses similar to the allergic disease groups. In the whole-blood culture stimulated by Dermatophagoides pteronyssinus, average IL-4 production did not differ significantly among the groups, but IL5 production resulting from stimulation was greater in the allergic disease groups (p<0.05). CONCLUSIONS: The allergic response pattern in group with filarial infection was similar to that of the groups with and without allergic diseases, but the response to IL-5 in the culture stimulated by D. pteronyssinus was an exclusive characteristic of the allergic group.


Asunto(s)
Brugia Malayi/inmunología , Filariasis Linfática/inmunología , Eosinófilos/inmunología , Hipersensibilidad Inmediata/inmunología , Células Th2/inmunología , Wuchereria bancrofti/inmunología , Adolescente , Animales , Antígenos Dermatofagoides/inmunología , Brasil/epidemiología , Células Cultivadas , Niño , Preescolar , Dermatophagoides pteronyssinus/inmunología , Filariasis Linfática/epidemiología , Enfermedades Endémicas , Femenino , Humanos , Hipersensibilidad Inmediata/epidemiología , Inmunoglobulina E/sangre , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Masculino , Enfermedades Desatendidas
8.
Environ Manage ; 61(2): 321-336, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29185008

RESUMEN

When the Amazonian rain forest is cut to create pasture, some of the original vegetal species survive clearing, even expressing their ability to invade agro-systems. It is true of the babassu palm, which can be considered, paradoxically, a natural resource by the "Interstate Movement of Babassu Fruit Breaker Women" or as native weed by land owners-farmers. To manage potential conflict of land uses, we study here the current density of this palm tree in different habitats, based on a combination of field data and remote sensing data. Firstly, we checked that the field survey methodology (i.e., counting free-trunk palm trees over 20 cm in circumference) provides density values compatible with those stemming from satellite images interpretation. We can see then that, a PA-Benfica Brazilian territory revealed an average density of the babassu lower in pastures (2.86 ind/ha) than in the dense forest (4.72 ind/ha) from which they originate and than in fallow land (4.31 ind/ha). We analyze in detail density data repartition in three habitats and we discuss results from the literature on the density of this palm tree versus its resilience at different developmental stages after forest clearing, depending on anthropogenic-or not-factors, including solar radiation, fire, weeding, clear cutting, burying fruit, and competition with forage grass. All these results can be exploited for the design of future management plans for the babassu palm and we think that the linked methodology and interdisciplinary approach can be extended to others palms and trees species in similar problematic issues.


Asunto(s)
Agricultura/métodos , Arecaceae , Bosque Lluvioso , Imágenes Satelitales , Biodiversidad , Brasil , Recolección de Datos/métodos , Incendios , Árboles
10.
Proc Natl Acad Sci U S A ; 111(40): 14372-7, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25246541

RESUMEN

Quantum spins placed on the corners of a square lattice can dimerize and form singlets, which then can be transformed into a magnetic state as the interactions between dimers increase beyond threshold. This is a strictly 2D transition in theory, but real-world materials often need the third dimension to stabilize long-range order. We use high pressures to convert sheets of Cu(2+) spin 1/2 dimers from local singlets to global antiferromagnet in the model system SrCu2(BO3)2. Single-crystal neutron diffraction measurements at pressures above 5 GPa provide a direct signature of the antiferromagnetic ordered state, whereas high-resolution neutron powder and X-ray diffraction at commensurate pressures reveal a tilting of the Cu spins out of the plane with a critical exponent characteristic of 3D transitions. The addition of anisotropic, interplane, spin-orbit terms in the venerable Shastry-Sutherland Hamiltonian accounts for the influence of the third dimension.

11.
Genet Mol Res ; 15(4)2016 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-27813610

RESUMEN

Most taxa in the Bignoniaceae have 2n = 40, but the basal clade Jacarandeae has 2n = 36, suggesting that x = 18 is the ancestral basic number for the family. Variations in heterochromatin band patterns in genera that are numerically stable, such as Jacaranda, could facilitate our understanding of the chromosomal and karyotypic evolution of the family. We characterized heterochromatin distributions in six Jacaranda species using chromomycin A3 (CMA) and 4'6-diamidino-2-phenylindole (DAPI). All of them had 2n = 36, including first counts for Jacaranda bracteata Bureau & K. Schum., Jacaranda irwinii A.H. Gentry, Jacaranda jasminoides (Thunb.) Sandwith, and Jacaranda rugosa A.H. Gentry. Their karyotypes had four to eight terminal CMA+/DAPI- bands per monoploid set. In the section Monolobos, Jacaranda brasiliana (Lam.) Pers. had eight terminal bands and Jacaranda mimosifolia D. Don had four; in the section Dilobos, J. bracteata had six bands per monoploid set, with the other species having five. While three species in the section Dilobos had the same number of terminal bands, J. irwinii had two additional pericentromeric bands and a proximal heterozygotic band, and J. bracteata had two distended CMA bands. The consistent records of 2n = 36 in Jacaranda may represent a plesiomorphic condition for the Bignoniaceae; therefore, the family originated from an ancestor with x = 18. However, 2n = 36 may represent a derived condition, and the family could have had an ancestral basic number of x = 20 that is still conserved in most representatives of the family.


Asunto(s)
Bignoniaceae/genética , Evolución Biológica , Cromosomas de las Plantas/genética , Heterocromatina/genética , Cariotipo , Metafase/genética , Especificidad de la Especie
12.
Am J Transplant ; 15(6): 1654-65, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25833197

RESUMEN

Children born to female kidney recipients are exposed to immunosuppressive drugs during gestation. Little is known about their immune system at birth or in the long term. Twenty-eight children born to female kidney recipients and 40 full-term children born to healthy mothers were evaluated. T, B, NK, NKT, γδT cells were assessed by flow cytometry and functional evaluation of T and dendritic cells after in vitro activation was performed at birth and at 8 months of age. At birth, infants born to female kidney recipients showed lower numbers of CD4+ T, NKT and intense reduction of B cells (median cells/mm(3) , transplant: 153.7 X control: 512.4; p < 0.001). There was also a reduced percentage of activated CD8+ T and of CD4+ regulatory T cells. Activated memory and exhausted memory B cells showed higher percentages among children exposed to immunosuppressors when compared to control group. At 8 months, most immune alterations were no longer observed, but four children still had low numbers of some lymphocyte subsets at this age. Children born to female kidney recipients had 4.351 (95% CI: 1.026-15.225; p = 0.046) higher risk of hospital admission in the first months of life-some, with severe clinical manifestations-than those born to healthy women.


Asunto(s)
Hospitalización/estadística & datos numéricos , Inmunofenotipificación , Infecciones/epidemiología , Trasplante de Riñón , Efectos Tardíos de la Exposición Prenatal/epidemiología , Receptores de Trasplantes , Inmunidad Adaptativa/efectos de los fármacos , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Edad Gestacional , Rechazo de Injerto/prevención & control , Humanos , Inmunidad Innata/efectos de los fármacos , Inmunosupresores/efectos adversos , Inmunosupresores/farmacología , Inmunosupresores/uso terapéutico , Lactante , Recién Nacido , Embarazo , Factores de Riesgo , Linfocitos T Reguladores/patología , Adulto Joven
13.
Genet Mol Res ; 14(4): 14479-87, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26600506

RESUMEN

Leprosy is a highly infectious disease endemic to underdeveloped countries. In Maranhão State, Northeastern Brazil, the hyperendemic rate of 56.11 cases/100,000 inhabitants increased the necessity of better understanding the epidemiological profile of this population, particularly regarding efficient methods for evaluating individuals residing with diagnosed patients to understand disease transmission and the risk of infection. In this study, we examined the percentage of contacts with positive indices for Mycobacterium leprae DNA and phenol-glycolipid-1 antigen (PGL-1). PGL-1 was analyzed by an enzyme-linked immunosorbent assay, the ML-Flow test, and polymerase chain reaction of oral and nasal secretions of 808 leprosy contacts from Maranhão. PGL-1 was detected in 14.0% of patients and differed by operational classification of the index case (P < 0.05). Seropositive results of ML-Flow were 15.0% and identified individuals with and without Bacillus Calmette-Guérin vaccine scars. Molecular diagnosis detected M. leprae DNA in 5.6% of oral samples and 4.6% of nasal tissues, and 87% of subjects resided with high bacillary load patients. This study reinforces the efficacy of combining molecular and serological techniques to identify potential bacillus carriers in the asymptomatic stage of infection, such as in household contacts, highlighting the importance of these meth-ods for monitoring hyperendemic populations.


Asunto(s)
Antígenos Bacterianos/aislamiento & purificación , Glucolípidos/aislamiento & purificación , Lepra/diagnóstico , Mycobacterium leprae/patogenicidad , Patología Molecular/métodos , Adolescente , Adulto , Antígenos Bacterianos/inmunología , Vacuna BCG , Brasil , Enfermedades Endémicas , Composición Familiar , Femenino , Glucolípidos/inmunología , Humanos , Lepra/epidemiología , Lepra/inmunología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Mycobacterium leprae/aislamiento & purificación , Pruebas Serológicas , Adulto Joven
14.
World J Microbiol Biotechnol ; 30(7): 1977-83, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24504708

RESUMEN

Kluyveromyces lactis strains are able to assimilate lactose. They have been used industrially to eliminate this sugar from cheese whey and in other industrial products. In this study, we investigated specific features and the kinetic parameters of the lactose transport system in K. lactis JA6. In lactose grown cells, lactose was transported by a system transport with a half-saturation constant (K s) of 1.49 ± 0.38 mM and a maximum velocity (V max) of 0.96 ± 0.12 mmol. (g dry weight)(-1) h(-1) for lactose. The transport system was constitutive and energy-dependent. Results obtained by different approaches showed that the lactose transport system was regulated by glucose at the transcriptional level and by glucose and other sugars at a post-translational level. In K. lactis JA6, galactose metabolization was under glucose control. These findings indicated that the regulation of lactose-galactose regulon in K. lactis was similar to the regulation of galactose regulon in Saccharomyces cerevisiae.


Asunto(s)
Kluyveromyces/metabolismo , Lactosa/metabolismo , Transporte Biológico/fisiología , Regulación Fúngica de la Expresión Génica , Cinética
15.
Vox Sang ; 104(3): 207-13, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23046429

RESUMEN

BACKGROUND AND OBJECTIVES: Platelet transfusions are performed almost entirely according to expert experience. This study assessed the effectiveness of a restrictive guideline to reduce platelet transfusions in preterm infants. METHODS: A retrospective cohort of preterm infants with a birth weight of <1500 g had been born in 2 periods. In Period 1, a transfusion was indicated for a platelet count of <50,000/ml in clinically stable neonates or <100,000/ml in bleeding or clinically unstable infants. In Period 2, the indications were restricted to <25,000/ml in clinically stable neonates, or <50,000/ml in newborns who were either on mechanical ventilation, subject to imminent invasive procedures, within 72 h following a seizure, or extremely premature and <7 days old. A count of <100,000/ml was indicated for bleeding or major surgery. RESULTS: Periods 1 and 2 comprised 121 and 134 neonates, respectively. The rates of ventricular haemorrhage and intrahospital death were similar in both periods. The percentage of transfused infants, the odds of receiving a platelet transfusion, the mean platelet count before transfusion and the percentage of transfusions with a platelet count >50,000/ml were greater in Period 1. Among thrombocytopenic neonates, the percentage of transfused neonates and the number of transfusions were similar in both groups. CONCLUSION: The restrictive guideline for platelet transfusions reduced the platelet count thresholds for neonatal transfusions without increasing the rate of ventricular haemorrhage.


Asunto(s)
Recuento de Plaquetas/normas , Transfusión de Plaquetas/normas , Guías de Práctica Clínica como Asunto , Plaquetas , Peso Corporal , Femenino , Humanos , Recién Nacido , Recién Nacido de muy Bajo Peso , Cuidado Intensivo Neonatal/organización & administración , Masculino , Proyectos Piloto , Transfusión de Plaquetas/métodos , Respiración Artificial , Estudios Retrospectivos , Convulsiones/terapia , Factores de Tiempo
16.
Genet Mol Res ; 12(4): 5124-33, 2013 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24301772

RESUMEN

Ancestry-informative markers (AIMs) are powerful tools for inferring the genetic composition of admixed populations. In this study, we determined the genetic ancestry of the Ouro Preto (Brazil) population and evaluated the association between ancestry and self-reported skin color. The genetic ancestry of 189 children and adolescents was estimated by genotyping 15 AIMs. The estimate of population admixture was determined using the Bayesian Markov Chain Monte Carlo (MCMC) method implemented in two different programs (STRUCTURE and ADMIXMAP). Volunteers self-reported their skin colors. The European ancestry contribution ranged from 0.503 to 0.539, the African contribution ranged from 0.333 to 0.425, and the Amerindian component ranged from 0.04 to 0.164. The relative contributions of African (P < 0.016) and European (P < 0.011) ancestry differed significantly among skin color groups, except between black and dark-brown groups. The population of Ouro Preto has a higher contribution of African ancestry compared to the mean for the southeast region of Brazil. Therefore, extrapolating the African ancestry contribution for southeastern Brazil to the Ouro Preto population would underestimate the actual value for this city. We also showed that self-reported skin color could be appropriate for describing the genetic structure of this particular population.


Asunto(s)
Etnicidad/genética , Genética de Población , Alelos , Brasil , Niño , Evolución Molecular , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Carácter Cuantitativo Heredable
17.
Int J Cosmet Sci ; 35(1): 69-77, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22970715

RESUMEN

Plants with antioxidant properties are beneficial for preventing the ageing events evoked by UV light, and numerous products based on Camellila sinensis (green tea) are commercially available, many of which claiming to contain bioactive compounds that would prevent UV-induced skin damage. In this study, we tested the efficacy of five commercial green tea extracts used to enrich cosmetic formulations for protecting human and mouse fibroblasts against UV radiation effects and compared with a fluid one prepared according to the Brazilian Pharmacopoeia recommendations. Taking into consideration that the ageing process can be accelerated by solar radiation by excessive free radical generation, leading to depletion of skin antioxidant defences, and its collapse caused by disruption of the metalloproteinase metabolism, we have used their individual (-)-epigallocathechin-3-gallate (EGCG) content, the catalase and SOD status and the matrix-degrading metalloproteases (MMP)-1, MMP-9 and MMP-13 levels as comparative parameters. The EGCG content of the commercial products showed wide variability, ranging from undetectable levels to 58.65 ± 1.12 µg mL(-1) , in contrast with the fluid extract (87.82 ± 1.35 µg mL(-1) ). Moreover, only the pharmacopoeic extract was able to significantly reduce MMP degradation while enhancing the levels of SOD and catalase. These results indicate, for the first time, that the methodologies for preparing herbal mixtures can interfere significantly with compounds endowed with photoprotective effects, and the efficacy of products containing C. sinensis extracts thought to act against effects of solar radiation can be compromised.


Asunto(s)
Extractos Vegetales/farmacología , Protectores contra Radiación/farmacología , Té/química , Rayos Ultravioleta , Animales , Antioxidantes/farmacología , Humanos , Técnicas In Vitro , Ratones
18.
Braz J Biol ; 83: e273069, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37646755

RESUMEN

Glyphosate is a herbicide commonly used in agriculture for weed control. Current agricultural production demands vast amounts of this product, which are applied by ground or aerial spraying. The concomitant aerial currents promote glyphosate drift to vegetated or urban areas. In this context, we hypothesized that the lichens, Parmotrema tinctorum and Usnea barbata, could be sensitive to the action of glyphosate and therefore be used to bio-indicate the presence of this herbicide in areas affected by drift. Since living organisms respond in different ways to the action of herbicides, our interest was also to indicate biological markers responsive to the action of glyphosate, through concentrations and exposure times of the thallus, besides identifying the most sensitive species. We evaluated the effect of different concentrations (0.0, 4.8, 9.6, and 19.2 mg L-1) and exposure times (24, 48, and 72 hours) to glyphosate on the morphoanatomy, photobiont vitality, photosynthetic efficiency, and oxidative metabolism of the thalli. We found that the lichens, P. tinctorum and U. barbata, respond to glyphosate stress, with prospects for use in the biomonitoring of pollutant dispersal from plantation areas. When using P. tinctorum as a bioindicator, lichen morphoanatomy, photobiont vitality, and photosynthetic pigment concentration were efficient biomarkers for the effect of concentration and exposure time. For U. barbata, the lichenic morphoanatomy and the activity of SOD and APX enzymes were essential tools to indicate the herbicide action. Parmotrema tinctotum, however, was characterized as more sensitive in bio-indicating the presence of this herbicide to diagnose the air quality in urban areas or vegetation sectors adjacent to agricultural environments.


Asunto(s)
Herbicidas , Líquenes , Usnea , Biomarcadores , Herbicidas/toxicidad , Glifosato
19.
J Chem Phys ; 136(5): 054502, 2012 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-22320746

RESUMEN

A neutron diffraction study was performed on the CD(4) : D(2)O structure H clathrate hydrate to refine its CD(4) fractional cage occupancies. Samples of ice VII and hexagonal (sH) methane hydrate were produced in a Paris-Edinburgh press and in situ neutron diffraction data collected. The data were analyzed with the Rietveld method and yielded average cage occupancies of 3.1 CD(4) molecules in the large 20-hedron (5(12)6(8)) cages of the hydrate unit cell. Each of the pentagonal dodecahedron (5(12)) and 12-hedron (4(3)5(6)6(3)) cages in the sH unit cell are occupied with on average 0.89 and 0.90 CD(4) molecules, respectively. This experiment avoided the co-formation of Ice VI and sH hydrate, this mixture is more difficult to analyze due to the proclivity of ice VI to form highly textured crystals, and overlapping Bragg peaks of the two phases. These results provide essential information for the refinement of intermolecular potential parameters for the water-methane hydrophobic interaction in clathrate hydrates and related dense structures.

20.
Int J Sports Med ; 33(8): 654-60, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22538549

RESUMEN

We purposed to study energy expenditure, power output and gross efficiency during kayak ergometer exercise in 12 elite sprint kayakers. 6 males (age 24.2±4.8 years, height 180.4±4.8 cm, body mass 79.7±8.5 kg) and 6 females (age 24.3±4.5 years, height 164.5±3.9 cm, body mass 65.4±3.5 kg), performed an incremental intermittent protocol on kayak ergometer with VO2 and blood lactate concentration assessment, a non-linear increase between power output and energy expenditure being observed. Paddling power output, energy expenditure and gross efficiency corresponding to VO2max averaged 199.92±50.41 W, 75.27±6.30 ml.kg - 1.min - 1, and 10.10±1.08%. Male kayakers presented higher VO2max, power output and gross efficiency at the VO2max, and lower heart rate and maximal lactate concentration than females, but no differences were found between genders regarding energy expenditure at VO2max. Aerobic and anaerobic components of energy expenditure evidenced a significant contribution of anaerobic energy sources in sprint kayak performance. Results also suggested the dependence of the gross efficiency on the changes in the amount of the aerobic and anaerobic contributions, at heavy and severe intensities. The inter-individual variance of the relationship between energy expenditure and the corresponding paddling power output revealed a relevant tracking for females (FDγ=0.73±0.06), conversely to the male group (FDγ=0.27±0.08), supporting that some male kayakers are more skilled in some paddling intensities than others.


Asunto(s)
Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Consumo de Oxígeno/fisiología , Resistencia Física/fisiología , Deportes/fisiología , Adulto , Eficiencia , Ergometría , Femenino , Humanos , Masculino , Navíos
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