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1.
Mech Adv Mat Struct ; 30(22): 4582-4596, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38014414

RESUMEN

This paper presents the numerical damage analysis of concrete structures using higher-order beam theories based on Carrera Unified Formulation (CUF). The concrete constitutive relation is modeled using continuum damage mechanics based on a modified Mazars concrete damage model, in which both the tensile and compressive softening behaviors are regularized with classical fracture energy methodology. An expression is proposed to estimate the characteristic length in higher-order beam theories, to prevent mesh dependency. Both softening constitutive laws and fracture energy calculations are obtained according to Model Code 2010. To assess the efficiency of the proposed model, three classical benchmark quasi-static experiments are taken for validation. From the comparison between numerical and experimental results, the proposed CUF model using continuum damage mechanics can present 3D accuracy with low computational costs and reduce the mesh dependency.

2.
Biomed Pharmacother ; 113: 108728, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30856536

RESUMEN

Glioblastoma, which is highly invasive and has a poor patient prognosis, is the most common type of brain tumor. Flavonoids have known antiproliferative and antineoplastic effects, such as apoptosis induction and tumor growth inhibition. We investigated the effects of treatment with three flavonoids (BAS-1, BAS-4, and BAS-6) isolated from the Amazon plant Brosimum acutifolium on the proliferation and migration of the C6 glioma cell line. Cytotoxicity was evaluated by MTT assay, and morphological changes were evaluated by phase-contrast microscopy and by transmission electron microscopy. Apoptosis was determined using Annexin V-FITC-propidium iodide (PI) staining. A hemolysis assay was used to evaluate plasma membrane injury. Antiproliferative effects were assessed by wound migration and colony formation assays. Mitochondrial transmembrane potential (ΔΨm) was determined using JC-1 dye and flow cytometry. To identify the flavonoid targets, western blotting was performed. BAS-1 and BAS-4 reduced C6 cell proliferation in a dose-dependent manner. BAS-6 showed no effect. Due to its high toxicity toward primary glial cells and its high hemolytic index, BAS-1 was not used in the remaining experiments. BAS-4 treatment did not induce cytotoxicity in primary glial cells; however, in glioma cells, it suppressed migration and invasion and led to apoptosis through mitochondrial damage, ΔΨm loss, cell cycle arrest, and reduced AKT phosphorylation, which is a component of the main cell survival pathway. We conclude that BAS-4 showed potential activity against glioma by inducing apoptosis mediated by ΔΨm loss and AKT pathway disruption, and future studies should further evaluate BAS-4 as a promising antineoplastic agent against glioblastoma.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Flavonoides/farmacología , Glioma/tratamiento farmacológico , Moraceae/química , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Flavonoides/administración & dosificación , Flavonoides/aislamiento & purificación , Citometría de Flujo , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Glioma/patología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Wistar
3.
Vet Parasitol ; 266: 96-102, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30736955

RESUMEN

Central nervous system (CNS) is the main site for encystment of Neospora caninum in different animal species. In this tissue, glial cells (astrocytes and microglia) modulate responses to aggression in order to preserve homeostasis and neuronal function. Previous data showed that when primary cultures of glial cells are infected with N. caninum, they develop gliosis and the immune response is characterized by the release of TNF and IL-10, followed by the control of parasite proliferation. In order to elucidate this control, three enzymatic systems involved in parasite-versus-host interactions were observed on a model of neuron/glia co/cultures obtained from rat brains. Indoleamine 2,3-dioxygenase (IDO), induced nitric oxide synthase (iNOS) responsible for the catabolism of tryptophan and arginine, respectively, and cycloxigenase (COX) were studied comparing their modulation by respective inhibitors with the number of tachyzoites or the immune response measured by the release of IL-10 and TNF. Cells were treated with the inhibitors of iNOS (1.5 mM L-NAME), IDO (1 mM 1-methyl tryptophan), COX-1 (1 µM indomethacin) and COX-2 (1 µM nimesulide) before infection with tachyzoites of N. caninum (1:1 cell: parasite). After 72 h of infection, immunocytochemistry showed astrogliosis and a significant increase in the number and length of neurites, compared with uninfected co-cultures, while an increase of IL-10 and TNF was verified. N. caninum did not change iNOS activity, but the inhibition of the basal levels of this enzyme stimulated parasite proliferation. Additionally, a significant increase of about 40% was verified in the IDO activity, whose inhibition caused 1.2-fold increase in parasitic growth. For COX-2 activity, infection of cultures stimulated a significant increase in release of PGE2 and its inhibition by nimesulide allowed the parasitic growth. These data indicate that iNOS, IDO and COX-2 control the proliferation of N. caninum in this in vitro model. On the other hand, the release of IL-10 by glia besides modulating the inflammation also allow the continuity of parasitism.


Asunto(s)
Ciclooxigenasa 2/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Neospora/crecimiento & desarrollo , Neuroglía/parasitología , Neuronas/parasitología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Animales , Células Cultivadas , Técnicas de Cocultivo , Inhibidores de la Ciclooxigenasa/farmacología , Dinoprostona/análisis , Interacciones Huésped-Parásitos , Indometacina/farmacología , Interleucina-10/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Neospora/efectos de los fármacos , Neuroglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas , Sulfonamidas/farmacología , Triptófano/análogos & derivados , Triptófano/farmacología , Factor de Necrosis Tumoral alfa/metabolismo
4.
J Endocrinol Invest ; 42(7): 797-807, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30465247

RESUMEN

PURPOSE: Metabolic syndrome (MS) and sarcopenia are associated with increased cardiovascular risk. No studies using dual-energy x-ray absorptiometry (DXA) have evaluated association between body composition (BC) changes and MS in adrenal incidentaloma (AI). Our aim was to analyse BC in non-functioning AI (NFAI) and intermediate phenotype (IP) relative to controls and to correlate with cortisol levels. METHODS: Cross-sectional study with 44 NFAI (serum cortisol ≤ 50 nmol/L after the overnight 1 mg dexamethasone suppression test), 27 IP (cortisol 51-138 nmol/L), and 41 controls (normal adrenal on imaging examination) using DXA. Autonomic cortisol secretion (cortisol > 138 nmol/L) was excluded from the study. BC data were compared using criteria for MS (World Health Organization, National Cholesterol Education Program-Adult Treatment Panel-III, American Association of Clinical Endocrinologists (AACE), and International Diabetes Federation). RESULTS: There was no significant difference in clinical data and body mass index (BMI) among the three groups. Waist circumference (WC) was larger in AI vs. controls (p < 0.01). Waist-to-hip ratio was higher in NFAI vs. controls and waist-to-height ratio was higher in IP vs. controls (p = 0.03 and p = 0.02, respectively). The frequency of MS was higher in AI vs. controls. BC was not different among the groups. Patients with AI there was a significant association of MS with both an increase in total fat and body fat index (all criteria), and a significant difference between MS and smaller BMI-adjusted lean mass (AACE, p = 0.036). No correlation of cortisol after 1 mg dexamethasone test with BC or MS. AI and WC were independently associated with MS. CONCLUSIONS: AI presented high frequency of MS and was independently associated with MS. Possible deleterious effects of cortisol secretion seem to initially affect the muscular system.


Asunto(s)
Absorciometría de Fotón/métodos , Neoplasias de las Glándulas Suprarrenales/complicaciones , Composición Corporal , Síndrome Metabólico/diagnóstico , Fenotipo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Síndrome Metabólico/etiología , Persona de Mediana Edad , Pronóstico , Adulto Joven
5.
J Phys Chem A ; 122(51): 9755-9760, 2018 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-30520626

RESUMEN

The photofragmentation dynamics of 1,1,1,2-tetrafluoroethane (R134a) with photon energies from 12 eV up to 320 eV, surrounding the C 1s edge is discussed. The ionic moieties were measured in coincidence with the ejected electrons (PEPICO mode), and detected as a function of the photon energy. Around the C K core edge, the fragmentation profiles are examined regarding the site specific excitation of the CH2FCF3 molecule. In the present case, site-selectivity is favored by the distinct chemical environments surrounding both C atoms. NEXAFS spectrum at the C 1s edge simulation has been obtained at the TDDFT level and excited state geometry optimization calculations have been performed at the inner-shell multiconfigurational self-consistent field level. Our observations indicate that the C(H2F) 1s excitation to a highly repulsive potential expels a fluorine atom leaving the heavier radical fragment C2F3H2* which relaxes to the fundamental state of the ion C2F3H2+. On the other hand, the excitation from the C(F3) 1s carbon to a repulsive state in the C-C bond, leads to a C-C bond cleavage, explaining the observed site specific fragmentation.

6.
Br J Oral Maxillofac Surg ; 56(10): 952-955, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30448357

RESUMEN

Our aim was to assess the association between the angle of impaction of the third molar and the position of the mandibular canal on cone-beam computed tomography (CT). We designed a retrospective study of 100 cone-beam CT images of 173 mandibular third molars that were obtained between January 2012 and December 2015, and recorded the angle of impaction of the third molar, the position of the mandibular canal in relation to the impacted tooth, and the potential contact between the roots of the tooth and the mandibular canal. Most third molars tilted mesially (n=33), while the mandibular canal was positioned below the roots of the third molar in most cases (n=73). Contact between the two was most likely when the mandibular canal was between (RR=1.49; 95% CI 1.27 to 1.75, p<0.001), or to the lingual side (RR=1.49; 95% CI 1.27 to 1.75, p<0.001) of the roots of the tooth. These outcomes indicate a greater likelihood of contact between the canal and the roots when the canal is between, and to the lingual side, of the roots. We found no association between the angle of impaction and the position of the canal. These findings illustrate the importance of surgical planning using complementary imaging tests such as cone-beam CT.


Asunto(s)
Mandíbula/patología , Tercer Molar/patología , Diente Impactado/patología , Adulto , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Nervio Mandibular/diagnóstico por imagen , Nervio Mandibular/patología , Tercer Molar/diagnóstico por imagen , Tercer Molar/cirugía , Radiografía Dental , Estudios Retrospectivos , Diente Impactado/diagnóstico por imagen
7.
Science ; 361(6405): 894-899, 2018 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-30139911

RESUMEN

The yellow fever virus (YFV) epidemic in Brazil is the largest in decades. The recent discovery of YFV in Brazilian Aedes species mosquitos highlights a need to monitor the risk of reestablishment of urban YFV transmission in the Americas. We use a suite of epidemiological, spatial, and genomic approaches to characterize YFV transmission. We show that the age and sex distribution of human cases is characteristic of sylvatic transmission. Analysis of YFV cases combined with genomes generated locally reveals an early phase of sylvatic YFV transmission and spatial expansion toward previously YFV-free areas, followed by a rise in viral spillover to humans in late 2016. Our results establish a framework for monitoring YFV transmission in real time that will contribute to a global strategy to eliminate future YFV epidemics.


Asunto(s)
Brotes de Enfermedades/prevención & control , Monitoreo Epidemiológico , Genómica/métodos , Fiebre Amarilla/prevención & control , Fiebre Amarilla/transmisión , Virus de la Fiebre Amarilla/aislamiento & purificación , Aedes/virología , Factores de Edad , Animales , Brasil/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Evolución Molecular , Humanos , Filogenia , Reacción en Cadena de la Polimerasa , Riesgo , Factores Sexuales , Análisis Espacio-Temporal , Fiebre Amarilla/epidemiología , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/clasificación , Virus de la Fiebre Amarilla/genética
8.
Curr Pain Headache Rep ; 21(7): 31, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28551735

RESUMEN

PURPOSE OF REVIEW: Headache is a common complaint among children and adolescents. School functioning is one of the most important life domains impacted by chronic pain in children. This review discusses the epidemiological and pathophysiological connections between headaches and school functioning including a suggested clinical approach. RECENT FINDINGS: The connection between recurrent and chronic headache and learning disabilities might be psychosocial (fear of failure) or anatomical (malfunctioning of the frontal and prefrontal areas). Only few population-based and clinical studies were done and good studies are still needed in order to understand the complex relationship better. However, relating to our patients' learning and school performance, history is crucial when a child with primary headaches is evaluated. Learning disabilities seem to have a high prevalence among children with primary headache syndromes especially migraine. The connection between the two is complex and might be either part of a common brain pathophysiology and/or a consequence of poor quality of life.


Asunto(s)
Escolaridad , Cefaleas Primarias/fisiopatología , Adolescente , Niño , Lóbulo Frontal/fisiopatología , Cefaleas Primarias/epidemiología , Cefaleas Primarias/psicología , Humanos , Aprendizaje , Discapacidades para el Aprendizaje/etiología , Trastornos Migrañosos/fisiopatología , Corteza Prefrontal/fisiopatología , Prevalencia , Calidad de Vida
9.
Opt Lett ; 41(13): 3126-9, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27367118

RESUMEN

The concept of non-Markovianity (NM) in quantum dynamics is still an open debate. Understanding how to generate and measure NM in specific models may aid in this quest. In quantum optics, an engineered electromagnetic environment coupled to a single atom can induce NM. The most common scenario of structured electromagnetic environment is an optical cavity, composed by a pair of mirrors. Here, we show how to generate and measure NM on a two-level system coupled to a one-dimensional waveguide with no mirrors required. The origin of the non-Markovian behavior lies in the initial state of the field, prepared as a single-photon packet. NM is shown to depend on two experimentally controllable parameters, namely, the linewidth of the packet and its central frequency. We relate the presence of NM to quantum interference. We also show how the two output channels of the waveguide provide distinct signatures of NM, both experimentally accessible.

10.
J Trace Elem Med Biol ; 33: 68-72, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26653745

RESUMEN

Selenium (Se) is an essential trace-element that becomes toxic when present at high concentrations. Little is known regarding Se effects on parameters such as oxidative stress biomarkers. The aim of the present study was to investigate the effects of acute selenium exposure on oxidative stress biomarkers in a model organism, zebrafish (Danio rerio). Fish were exposed to selenium selenite at 1mgL(-1). Reduced glutathione (GSH), and metallothionein (MT) concentrations were determined in liver, kidney and brain, with MT also being determined in bile. Essential metals and trace-elements were also determined by inductively coupled mass spectrometry (ICP-MS) in order to verify possible metal homeostasis alterations. GSH concentrations in liver, kidney and brain increased significantly (1.05±0.03µmolg(-1) ww, 1.42±0.03µmolg(-1) ww and 1.64±0.03µmolg(-1) ww, respectively) in the Se-exposed group when compared to the controls (0.88±0.05µmolg(-1) ww, 0.80±0.04µmolg(-1) ww and 0.89±0.03µmolg(-1) ww for liver, kidney and brain, respectively). MT levels in Se-exposed liver (0.52±0.03µmolg(-1) ww) decreased significantly in comparison to the control group (0.64±0.02µmolg(-1) ww), while levels in bile increased, albeit non-significantly. This is in accordance with previous studies that indicate efficient biliary MT action, leading to a rapid metabolism and elimination of contaminants from the body. Levels in the brain increased significantly after Se-exposure (0.57±0.01µmolg(-1) ww) when compared to the control group (0.35±0.03µmolg(-1) ww) since this organ does not present a detoxification route as quick as the liver-gallbladder route. Several metal and trace-elements were altered with Se-exposure, indicating that excess of selenium results in metal dyshomeostasis. This is the first report on metal dyshomeostasis due to Se-exposure, which may be the first step in the mechanism of action of selenium toxicity, as is postulated to occur in certain major human pathophysiologies.


Asunto(s)
Biomarcadores/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ácido Selenioso/farmacología , Selenio/farmacología , Oligoelementos/metabolismo , Pez Cebra/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Glutatión/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Metalotioneína/metabolismo , Modelos Animales , Especificidad de Órganos/efectos de los fármacos , Espectrofotometría Atómica
11.
J Endocrinol Invest ; 38(11): 1159-66, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25957829

RESUMEN

PURPOSE: Ipilimumab is a human monoclonal antibody against cytotoxic T-lymphocyte antigen 4 available as an immunotherapy mainly for advanced melanoma. It induces an activation of T cells, resulting in an immune-mediated anti-tumor response and also immune-related adverse events, including hypophysitis. The aim of this review is to identify and discuss features concerning ipilimumab-induced hypophysitis (IIH). DESIGN: A MEDLINE research of all years of publication of IIH was conducted. We gathered information regarding clinical, radiologic and laboratory features of 71 cases recorded in the literature. RESULTS: In our review, IIH was more frequent among older and male patients. Fatigue and headache were the most frequent initial clinical manifestations of IIH and enlargement of the pituitary gland at MRI was present in the majority of patients. Those who received more than 3 cycles of ipilimumab had more fatigue (p = 0.04) and arthritis (p = 0.04). Adrenal insufficiency was more prevalent in men (p = 0.007). Glucocorticoid therapy and hormone replacement were required in most patients and pituitary function recovery was uncommon. Low prolactin at diagnosis tended to predict permanent pituitary dysfunction (p = 0.07). CONCLUSION: Hypopituitarism as a consequence of IIH, if not promptly recognized, can lead to potentially fatal events, such as adrenal insufficiency. IIH can be easily managed with glucocorticoids and hormonal replacement; therefore, physicians should be familiar with the key aspects of this condition. More studies to develop screening protocols and therapeutic intervention algorithms should be performed to decrease morbidity related to IIH.


Asunto(s)
Anticuerpos Monoclonales/efectos adversos , Hipopituitarismo/inducido químicamente , Factores Inmunológicos/efectos adversos , Melanoma/tratamiento farmacológico , Enfermedades de la Hipófisis/inducido químicamente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Ipilimumab , Masculino , Persona de Mediana Edad
12.
J Inorg Biochem ; 140: 160-6, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25108188

RESUMEN

Solid-state compounds of the general formulae [ML3] (M=Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y; L=ketoprofen) were synthesized and characterized using infrared, diffuse reflectance and luminescence spectroscopies. IR data suggested that the carboxylate group in ketoprofen is coordinated to the metals as a bidentate ligand. The triplet state energy level was determined using the Gd(3+) complex, which exhibited a ketoprofen blue luminescence when excited in the UV region. The compound containing Tb(3+) ion was sensitized by the ligand and emitted in the green region of the visible spectrum. On the other hand, for the analogous species containing the dysprosium ion, a competition for luminescence between the Dy(3+) and the ligand levels was observed. Finally, Tm(3+) complex exhibits only ligand luminescence. These optical behaviors are discussed based on rare earth energy diagrams. In addition, the compounds were evaluated for their anti-inflammatory activities. All the compounds showed a higher production of H2O2 and IL-10 than the ketoprofen, suggesting that the compounds exhibited an immunomodulatory effect and this opens up new perspectives for immunotherapeutic approaches.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Cetoprofeno/farmacología , Elementos de la Serie de los Lantanoides/química , Itrio/química , Células Cultivadas , Humanos , Técnicas In Vitro , Luminiscencia , Espectrofotometría Infrarroja
13.
Genet Mol Res ; 12(4): 5057-71, 2013 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24301767

RESUMEN

Chromobacterium violaceum is a Gram-negative proteobacteria found in water and soil; it is widely distributed in tropical and subtropical regions, such as the Amazon rainforest. We examined protein expression changes that occur in C. violaceum at different growth temperatures using electrophoresis and mass spectrometry. The total number of spots detected was 1985; the number ranged from 99 to 380 in each assay. The proteins that were identified spectrometrically were categorized as chaperones, proteins expressed exclusively under heat stress, enzymes involved in the respiratory and fermentation cycles, ribosomal proteins, and proteins related to transport and secretion. Controlling inverted repeat of chaperone expression and inverted repeat DNA binding sequences, as well as regions recognized by sigma factor 32, elements involved in the genetic regulation of the bacterial stress response, were identified in the promoter regions of several of the genes coding proteins, involved in the C. violaceum stress response. We found that 30 °C is the optimal growth temperature for C. violaceum, whereas 25, 35, and 40 °C are stressful temperatures that trigger the expression of chaperones, superoxide dismutase, a probable small heat shock protein, a probable phasing, ferrichrome-iron receptor protein, elongation factor P, and an ornithine carbamoyltransferase catabolite. This information improves our comprehension of the mechanisms involved in stress adaptation by C. violaceum.


Asunto(s)
Adaptación Biológica , Proteínas Bacterianas/metabolismo , Chromobacterium/metabolismo , Proteómica , Estrés Fisiológico , Temperatura , Adaptación Biológica/genética , Proteínas Bacterianas/genética , Respiración de la Célula , Chromobacterium/genética , Chromobacterium/crecimiento & desarrollo , Fermentación , Regulación Bacteriana de la Expresión Génica , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Sistemas de Lectura Abierta , Regiones Promotoras Genéticas , Proteómica/métodos , Estrés Fisiológico/genética
14.
Rev. andal. med. deporte ; 6(4): 151-160, dic. 2013.
Artículo en Español | IBECS | ID: ibc-118598

RESUMEN

Los indicadores de la valoración de la maduración biológica son ampliamente utilizados en diversas áreas. Proporcionan información relevante que permite determinar el ritmo o tiempo de maduración individual. El uso y la aplicación varía entre las técnicas, sin embargo, todos tienen un objetivo común, la clasificación de los niños y adolescentes en estadios de maduración. En este sentido, el objetivo de la presente revisión fue describir los indicadores de maduración biológica e indagar los posibles usos y aplicaciones dentro del ámbito escolar. Se concluye que a) la mayoría de los estudios coinciden en especificar que la maduración esquelética o edad ósea es el indicador más útil, aunque la predicción del pico de velocidad de crecimiento propuesta por Mirwald et al. (2002) es un indicador que permite valorar a poblaciones escolares de forma transversal y b) la valoración de la maduración, independientemente del tipo de metodología puede ser aplicada en el área clínica, la escuela, en el deporte y en la calidad de vida, como un medio de clasificación de grupos de trabajo para homogeneizar a los niños y adolescentes en circunstancias deportivas y no deportiva (AU)


The indicators for the assessment of biological maturation are widely used in various fields. Provide relevant information for determining the rate or time of individual maturation. The use and application varies between techniques, however, all have a common goal, the classification of children and adolescents in maturation stages. In this sense, the objective of this review was to describe indicators of biological maturation and investigate the possible uses and applications within the school. We conclude that a) most studies agree that specify skeletal maturity or bone age is the most useful indicator, although predicting the peak growth rate given by Mirwald et al. (2002) is an indicator for assessing school populations transversely, and b) the assessment of maturation, regardless of the methodology can be applied in the clinic, school, sports and quality of life as a means of classifying groups working to unify children and adolescents in circunstances competition and non-sports (AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Maduración Sexual/fisiología , Calidad de Vida , Deportes/fisiología , Deportes/estadística & datos numéricos , Deportes/tendencias , Actividad Motora/fisiología , Nutrición del Niño , Deportes/educación , Deportes/normas , Desempeño Psicomotor/fisiología , Fenómenos Fisiológicos Nutricionales Infantiles/fisiología
15.
Rev. andal. med. deporte ; 6(3): 108-114, sept. 2013.
Artículo en Portugués | IBECS | ID: ibc-113972

RESUMEN

Objetivo. As modificações que ocorrem com os jovens nas idades anteriores ao pico de velocidade de crescimento (PVC) podem influenciar de maneira direta o seu desempenho nas atividades esportivas. Considerando esse pressuposto, o objetivo deste estudo foi analisar o efeito da maturação somática nas variáveis motoras e corporais de jovens futebolistas. Método. Os 45 sujeitos foram divididos em três grupos de acordo com a maturação somática e submetidos à avaliação antropométrica e a uma bateria de testes que analisaram a flexibilidade (banco de Wells), a potência aeróbia (Yoyo endurance teste, nível 1) e a potência anaeróbia (salto horizontal e vertical). Resultados. Os resultados da análise de variância demonstram que o desempenho no salto vertical com contra movimento (F = 5,10 e p = 0,01) e no salto horizontal (F = 7,19 e p = 0,002) é influenciado pelo nível maturacional, o mesmo ocorrendo para a flexibilidade (F = 6,83 e p = 0,02). Por outro lado, o desempenho no teste de potência aeróbia não foi afetado pelo nível maturacional. As variáveis corporais somatotipo e o recíproco do índice ponderal se mantiveram estáveis independentemente do grau de maturação; apenas foram verificadas diferenças nos valores corporais para o IMC. Conclusão: Assim, pode-se concluir que a determinação dos estágios maturacionais dada pelos anos em relação ao PVC (APVC) dentro de uma determinada faixa etária pode ser um valioso instrumento de orientação para técnicos e treinadores na adequação dos treinamentos em função da real condição funcional de seus jovens atletas(AU)


Objective. The changes in young people at ages preceding the peak height velocity (PHV) can influence their performance in sports. Taken this issue into account, this study aimed to analyze the effect of maturity level on body composition and motor performance in young soccer players. Methods. The 45 subjects were divided into three groups according to somatic maturation and were submitted to anthropometric assessment and to a battery of tests that assessed flexibility (Wells' bench), aerobic power (Yoyo endurance test level 1) and anaerobic power (horizontal and vertical jumps). Results. The results of ANOVA indicate that performance in vertical jump with counter movement (F = 5.10, p = 0.01), standing long jump (F = 7.19, p = 0.002) and flexibility (F = 6.83, p = 0.02) are influenced by the level of maturation status. On the other hand, the performance in the aerobic power test was not affected by maturity status. The somatotype and the reciprocal of ponderal index variables remained steady regardless the degree of maturity; differences were only observed in body mass index values (BMI). Conclusion. Thus, we can conclude that the determination of maturational stages by means of years from PHV can be a valuable tool in order to aid coaches and trainers planning and monitoring training related to the actual functional condition of young athletes(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Fútbol/fisiología , Fútbol/psicología , Somatotipos/fisiología , Somatotipos/psicología , Biotipología , Educación y Entrenamiento Físico/métodos , Educación y Entrenamiento Físico/normas , Educación y Entrenamiento Físico/tendencias , Fútbol/normas , Fútbol/tendencias , Educación y Entrenamiento Físico/organización & administración , Antropometría/instrumentación , Antropometría/métodos
16.
Rev. andal. med. deporte ; 6(2): 66-72, jun. 2013. tab, ilus
Artículo en Español | IBECS | ID: ibc-113101

RESUMEN

Objetivo. Comparar el crecimiento físico de escolares a moderada altitud con las normas de referencia propuestas por Frisancho y Tracer para el área muscular del brazo por estatura y de Frisancho para el área muscular del brazo por edad. Método. Se realizó un estudio transversal en escolares de zonas urbanas de la provincia de Arequipa (Perú). La muestra se estratificó por edad y sexo, siendo 473 hombres y 482 mujeres con un rango de edad de 6 a12 años, pertenecientes al nivel primario del sistema educativo peruano de condición socioeconómica media. Se evaluaron las variables antropométricas de peso, estatura, circunferencia del brazo y pliegue tricipital, así como el área muscular del brazo para la estatura y para la edad. Los datos se compararon a través de escores Z y de acuerdo con la fracción: 100 log (percentil de la referencia/percentil calculado). Las diferencias entre la muestra estudiada y la referencia fueron analizados por medio del test t para muestras apareadas con una significancia de p < 0,001. Resultados. Los valores de la referencia de las áreas musculares del brazo en relación a la estatura y edad son superiores en comparación con los escolares de zonas con moderada altitud. Se observó 2 años de retraso en hombres y mujeres de acuerdo a la comparación con el área muscular por edad. Del mismo modo, utilizando el área muscular por estatura se verificó un atraso de 17cm en los hombres y de 20cm en las mujeres. Conclusión. En general, los resultados sugieren retraso sobre el crecimiento físico lineal y muscular, atribuyéndose este fenómeno a factores medio-ambientales como la altitud(AU)


Objective. To compare the physical growth of schoolchildren to moderate altitude with reference standards proposed by Frisancho and Tracer for arm muscle area by height and Frisancho for arm muscle area by age. Method. A cross-sectional study of urban schoolchildren in the province of Arequipa (Perú). The sample was stratified by age and sex, with 473 men and 482 women ranging in age from 6 to 12 years for belonging to the education system at primary level socioeconomic status Peruvian media. Anthropometric variables were assessed weight, height, arm circumference and triceps skinfold and arm muscle area for height and age. Data were compared by Z scores according to the fraction: 100 log (percentile of the reference / percentile calculated). The differences between the sample and reference were analyzed by the paired t test with a significance of p < 0.001. Results. The values of the reference arm muscle areas in relation to height and age are higher in comparison with students of moderate altitude. Was observed 2 years behind men and women according to the comparison with age-muscle area. Similarly, using the muscle area by height 17cm lag was observed in men and 20cm in women. Conclusions. Overall, the results suggest the physical growth retardation and muscle linear, attributing this phenomenon to environmental factors such as altitude(AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Estatura por Edad , Altitud , Antropometría/métodos , Pesos y Medidas Corporales/métodos , Desarrollo Infantil/fisiología , Índice de Masa Corporal , Estudios Transversales/métodos , Estudios Transversales/tendencias , Estudios Transversales , Factores Socioeconómicos , 24436 , Crecimiento/fisiología
17.
Talanta ; 104: 187-92, 2013 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-23597908

RESUMEN

The present speciation method reports the determination of inorganic arsenic forms, using metallic furnace hydride generation atomic absorption spectrometry. The inorganic As speciation is carried out using mild conditions for hydride formation, such as slightly acid pH media (4.50) and low tetrahydridoborate(1-) concentration (0.1% (w/v)). Limits of detection and quantification of 2.0 and 6.6 µg L(-1) of iAs(III) are obtained using optimized conditions. Additionally, microwave-assisted extraction using water as solvent is carried out to provide the appropriate environment for As species extraction as well as impeding inter-conversion between species. With these analytical strategies, As was accurately determined (at 99.9% confidence level) in water and plankton samples.


Asunto(s)
Arsénico/análisis , Plancton/química , Contaminantes Químicos del Agua/análisis , Arsénico/química , Microondas , Oxidación-Reducción , Espectrofotometría Atómica , Contaminantes Químicos del Agua/química
18.
Nutr. clín. diet. hosp ; 33(1): 31-37, ene.-abr. 2013. graf, tab
Artículo en Español | IBECS | ID: ibc-111577

RESUMEN

Objetivo: Comparar el crecimiento físico de peso y estatura de gimnastas de rítmicas de elite con la referencia de la Organización mundial de la Salud y determinar el estado nutricional a través de las áreas muscular y grasa del brazo, propuestos por Frisancho. Material y métodos: Fueron estudiadas 136 gimnastas de rítmicas de elite de Brasil. Las atletas fueron seleccionadas de forma no-probabilística (intencional). Las variables antropométricas valoradas fueron peso, estatura, estatura tronco-cefálica, circunferencia del brazo relajado y pliegue tricipital del brazo derecho. El peso y estatura fueron comparados con la referencia de la Organización Mundial de la Salud y el estado nutricional fue valorado por el área muscular y grasa propuestos por Frisancho. Resultados: Las gimnastas muestran bajos valores de peso corporal (p<0,05) y similar estatura en relación a la referencia de la OMS (p>0,05). Respecto al estado nutricional, se observó que el 13,5% se encuentran en riesgo de desnutrición y 12,5% con desnutrición en función de la reserva de proteína. Para el caso de la reserva calórica, el 11,5% se encuentra con riesgo de desnutrición y el 12,5% con desnutrición, respectivamente. En general, las gimnastas presentan valores similares de área muscular y bajos valores de área grasa en relación a la referencia cuando comparados con el p-50. Conclusión: Los resultados sugieren que las jóvenes de esta modalidad deportiva presentan bajos valores de reserva calórica debido a alta intensidad de entrenamiento a los que están expuestos (AU)


Objective: To compare the physical growth of weight and height of elite rhythmic gymnasts with reference to the World Health Organization and determine the nutritional status through muscle and fat areas of arm, proposed by Frisancho. Material and Methods: We studied 136 elite rhythmic gymnasts from Brazil. The athletes were selected in a non-probabilistic (intentional). The anthropometric variables evaluated were weight, height, height-cephalic trunk, arm circumference and triceps skinfold relaxed right arm. Weight and height were compared with the reference of the World Health Organization and nutritional status was assessed by muscle and fat area proposed by Frisancho. Results: The gymnasts are low in body weight (p <0.05) and similar height in relation to the WHO reference (p> 0.05). Regarding nutritional status, we observed that 13.5% are at risk of malnutrition and malnutrition 12.5% depending on the subject protein. In the case of caloric reserves, 11.5% are at risk of malnutrition and malnutrition 12.5%, respectively. In general, similar values gymnasts muscle area and low values of fat area in relation to the reference when compared to the p-50. Conclusion: The results suggest that young people of this sport have low caloric values of reserves due to high intensity training to which they are exposed (AU)


Asunto(s)
Humanos , Femenino , Niño , Adolescente , Crecimiento , Gimnasia/fisiología , Estado Nutricional , Trastornos Nutricionales/epidemiología , Desarrollo Infantil , Rendimiento Atlético/fisiología
19.
Int Endod J ; 46(8): 700-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23442003

RESUMEN

Diabetes mellitus (DM) is one of the most common metabolic disorders. DM is characterized by hyperglycaemia, resulting in wound healing difficulties and systemic and oral manifestations, which have a direct effect on dental pulp integrity. Experimental and clinical studies have demonstrated a higher prevalence of periapical lesions in patients with uncontrolled diabetes. The influence of DM on periapical bone resorption and its impact on dental intervention of such patients are reviewed, and its aetiology and pathogenesis are analysed at molecular level. Pulps from patients with diabetes have the tendency to present limited dental collateral circulation, impaired immune response, increased risk of acquiring pulp infection (especially anaerobic ones) or necrosis, besides toothache and occasional tendency towards pulp necrosis caused by ischaemia. In regard to molecular pathology, hyperglycaemia is a stimulus for bone resorption, inhibiting osteoblastic differentiation and reducing bone recovery. The relationship between poorly controlled diabetes and bone metabolism is not clearly understood. Molecular knowledge about pulp alterations in patients with diabetes could offer new therapeutic directions. Knowledge about how diabetes affects systemic and oral health has an enduring importance, because it may imply not only systemic complications but also a higher risk of oral diseases with a significant effect on pulp and periapical tissue.


Asunto(s)
Complicaciones de la Diabetes , Periodontitis Periapical/complicaciones , Pulpitis/complicaciones , Pérdida de Hueso Alveolar/complicaciones , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/fisiopatología , Humanos , Hiperglucemia/complicaciones , Factores de Riesgo , Tratamiento del Conducto Radicular
20.
Rev. bras. plantas med ; 15(4,supl.1): 717-726, 2013. graf
Artículo en Portugués | LILACS | ID: lil-700010

RESUMEN

O objetivo deste trabalho foi realizar a caracterização físico-química do pó e da tintura, e análise por espectrofotometria e cromatografia do extrato seco de Peperomia pellucida L. (H. B. K.). As metodologias seguiram a Farmacopéia Brasileira IV ed., com exceção da prospecção química, da espectrofotometria, da obtenção do perfil cromatográfico do extrato seco, e determinação do resíduo seco. A prospecção química revelou a presença de saponinas espumídicas; açúcares redutores; proteínas e aminoácidos; fenóis; taninos; flavonóides; esteróides e triterpenóides. Na análise por CCD, o melhor perfil da fração flavonoídica foi obtido com MeOH/CHOOH (90:10). Foi confirmada, através de CLAE, a presença de 3',4',7-tri-O-metoxiflavona no extrato seco deste material vegetal. Os resultados obtidos contribuem para a determinação de especificações de uma futura monografia em Farmacopéias da Peperomia pellucida L. (H.B.K.).


The aim of this study was the physical chemical characterization of the powder and the tincture, and the chromatographic and spectrophotometric analysis of the Peperomiapellucida L. (H. B. K.) dry extract. The methodology followed the Farmacopeia Brasileira IV ed., except for the chemical prospection, the chromatographic profile obtained and the spectrophotometry of the dry extract, and determination of dried residues. The chemical prospection revealed the presence of foaming saponins; reducing sugars; proteins and amino acids; phenols; tannins; flavonoids; steroids and triterpenoids; depsideos and depsidones. The best profile from TLC for flavonoidic fraction was obtained with methanol/formic acid (90:10 v/v). HPLC confirmed the presence of 3 ',4',7-tri-methoxyflavone in the dry extract of the plant material. The results obtained in this work should contribute for the determination of specifications for a future monograph on Peperomia pellucida L. (H.B.K.).


Asunto(s)
Espectrofotometría , Peperomia/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos , Desecación/instrumentación , Características del Estudio
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