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1.
J Physiol ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687681

RESUMEN

Altered autonomic input to the heart plays a major role in atrial fibrillation (AF). Autonomic neurons termed ganglionated plexi (GP) are clustered on the heart surface to provide the last point of neural control of cardiac function. To date the properties of GP neurons in humans are unknown. Here we have addressed this knowledge gap in human GP neuron structure and physiology in patients with and without AF. Human right atrial GP neurons embedded in epicardial adipose tissue were excised during open heart surgery performed on both non-AF and AF patients and then characterised physiologically by whole cell patch clamp techniques. Structural analysis was also performed after fixation at both the single cell and at the entire GP levels via three-dimensional confocal imaging. Human GP neurons were found to exhibit unique properties and structural complexity with branched neurite outgrowth. Significant differences in excitability were revealed between AF and non-AF GP neurons as measured by lower current to induce action potential firing, a reduced occurrence of low action potential firing rates, decreased accommodation and increased synaptic density. Visualisation of entire GPs showed almost all neurons are cholinergic with a small proportion of noradrenergic and dual phenotype neurons. Phenotypic distribution differences occurred with AF including decreased cholinergic and dual phenotype neurons, and increased noradrenergic neurons. These data show both functional and structural differences occur between GP neurons from patients with and without AF, highlighting that cellular plasticity occurs in neural input to the heart that could alter autonomic influence on atrial function. KEY POINTS: The autonomic nervous system plays a critical role in regulating heart rhythm and the initiation of AF; however, the structural and functional properties of human autonomic neurons in the autonomic ganglionated plexi (GP) remain unknown. Here we perform the first whole cell patch clamp electrophysiological and large tissue confocal imaging analysis of these neurons from patients with and without AF. Our data show human GP neurons are functionally and structurally complex. Measurements of action potential kinetics show higher excitability in GP neurons from AF patients as measured by lower current to induce action potential firing, reduced low firing action potential rates, and decreased action potential accommodation. Confocal imaging shows increased synaptic density and noradrenergic phenotypes in patients with AF. Both functional and structural differences occur in GP neurons from patients with AF that could alter autonomic influence on atrial rhythm.

2.
Crit Rev Food Sci Nutr ; 62(7): 1765-1781, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33242978

RESUMEN

Due to the increasing population, there is high concern about whether the current food system will be able to provide enough healthy food for 10 billion people by 2050. The general opinion is that it is possible to feed this population, but the food system requires major transformations on behalf of promoting sustainability, reducing food waste and stimulating a change toward diets healthy for humans and also sustainable for the planet. This article will review some detected problems in food production and consumption. In food production, current problems like destruction of land ecosystems, overfishing or generation of high amounts of residues stand out. Some solutions have been described, such as implement the agroecology, improve productivity of aquaculture or re-valorization of by-products. In food consumption, the main problems are the food fraud and the unhealthy dietary patters, whose main solutions are the standardization along food chain and education on healthy lifestyles. Concluding, food system should change toward more sustainable practices and behaviors in other to ensure the subsistence of the present and the future generations.


Asunto(s)
Alimentos , Eliminación de Residuos , Conservación de los Recursos Naturales , Ecosistema , Explotaciones Pesqueras , Abastecimiento de Alimentos , Humanos
3.
Genet Mol Res ; 16(3)2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28973753

RESUMEN

Schizolobium parahyba var. amazonicum (Fabaceae) is an arboreal species, endemic to the Amazon Rainforest, popularly known as paricá. It is used on a commercial scale in the timber sector, pulp and paper production, reclamation projects in degraded and landscaped areas. However, there is no availability of genetically improved material selected for the environmental conditions of the State of Espírito Santo, Brazil. In this sense, the present study aimed to characterize the genetic diversity in a population of S. amazonicum, established in a forest area in the southern region of the State of Espírito Santo, using inter-simple sequence repeat (ISSR) molecular markers. DNA samples from 171 individuals were analyzed using 11 ISSR primers, which generated 79 polymorphic bands in a total of 136 fragments (58%). The polymorphic information content performed for the ISSR markers revealed a mean of 0.37, classifying them as moderately informative. The number of loci found (N = 79) was greater than that established as the optimal number (N = 69) for the analyses. High genetic diversity was found with the parameters, genetic diversity of Nei (HE = 0.375) and Shannon index (I = 0.554). The data demonstrated in the dendrogram, based on the UPGMA cluster analysis, corroborated by the Bayesian analysis performed by the STRUCTURE program, which indicated the formation of two distinct clusters (K = 2). One of the groups was formed with the majority of the individuals (153 genotypes) and the second with the minority (18 genotypes). The results revealed high genetic diversity in the population of S. amazonicum evaluated in the present study, determining the potential of the population to be used as an orchard for seed collection and production of seedlings with confirmed genetic variability.


Asunto(s)
Fabaceae/genética , Polimorfismo Genético , Brasil , Bosques , Repeticiones de Microsatélite
4.
Genet Mol Res ; 16(2)2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28613383

RESUMEN

The Alcantarea patriae is a Bromeliaceae endemic to the inselbergs of the Atlantic Forest. This taxon, described in the year of 2007 by Versieux & Wanderley, presents restricted and fragmented distribution outside conservation units. Studies to evaluate the genetic structure of its populations can contribute to the conservation and management strategies for the species. In this study, 31 microsatellite markers, descriptive to six different Bromeliaceae species, were evaluated by cross-amplification tests in 20 individuals of A. patriae. The individuals were collected in the district of Vila Cruzeiro, in the municipality of Jerônimo Monteiro. Twelve markers were polymorphic and 10 monomorphic, with an amplification success rate of 71%. The displayed polymorphism information content was considered high, indicating that the selected markers are informative. The values found for the fixation index were positive and indicated the occurrence of inbreeding. The mean number of alleles was 4.66 (3-6), the mean expected and observed heterozygosities were 0.6605 and 0.4618, respectively. The detection of polymorphic markers was important for future studies of diversity and genetic structuring of natural populations and for germplasm bank creation aiming to contribute to in situ and ex situ conservations of A. patriae.


Asunto(s)
Bromeliaceae/genética , Repeticiones de Microsatélite , Amplificación de Genes , Frecuencia de los Genes , Heterocigoto , Endogamia , Polimorfismo Genético
5.
J Oral Rehabil ; 41(2): 108-14, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24666269

RESUMEN

The aim of this study was to investigate the biomechanical behaviour of maxillary premolar teeth regarding root morphology and abfraction depth, submitted to axial and oblique occlusal load. The investigation was conducted using 3D finite element analysis and strain gauge test. Sound maxillary premolar single and double root were selected for 3D model generation. The teeth were scanned for external morphology data acquisition. The 3D geometry was stored in *.STL and exported to Bio-CAD software (Rhinoceros-3D) to model generation. Mesh generation, mechanical properties and boundary conditions were performed in finite element software (Femap, Noran Engineering, USA). Twelve models were generated: sound tooth, 1.25 and 2.5 mm abfraction teeth. 100N compressive static load was applied: axially and 45° angle to the long axis on the palatine surface of the buccal cusp. Two strain gauges were bonded on the teeth mounted in a mechanical testing machine. Von Mises criterion showed that the double-root teeth associated with 2.5 mm abfraction and oblique loading presented higher stress values. Axial loading associated with single-root teeth propitiated the lowest stress rates. Double root sound 1.25 and 2.5 mm abfraction teeth associated with oblique loading showed the highest strain values (µS): 692.6, 1043.31 and 1236.14, respectively. Single root sound 1.25 and 2.5 mm abfraction teeth associated with oblique loading showed 467.10, 401.51 and 420.98 strain values, respectively. Axial loading showed lower strain rates, ranging from 136.12 to 366.91. The association of deep lesions, oblique loading and double-root tooth promoted higher stress and strain concentration.


Asunto(s)
Diente Premolar/fisiopatología , Fuerza de la Mordida , Análisis del Estrés Dental/métodos , Estrés Mecánico , Raíz del Diente/fisiopatología , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Maxilar
6.
Front Nutr ; 11: 1340121, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38628271

RESUMEN

Consumers are increasingly interested in food products with high nutritional value and health benefits. For instance, fish consumption is linked with diverse positive health benefits and the prevention of certain widespread disorders, such as obesity, metabolic syndrome, or cardiovascular diseases. These benefits have been attributed to its excellent nutritional value (large amounts of high-quality fatty acids, proteins, vitamins, and minerals) and bioactive compounds, while being relatively low-caloric. Atlantic bluefin tuna (Thunnus tynnus) is one of the most consumed species worldwide, motivated by its good nutritional and organoleptic characteristics. Recently, some organizations have proposed limitations on its consumption due to the presence of contaminants, mainly heavy metals such as mercury. However, several studies have reported that most specimens hold lower levels of contaminants than the established limits and that their richness in selenium effectively limits the contaminants' bioaccessibility in the human body. Considering this situation, this study aims to provide baseline data about the nutritional composition and the latest evidence regarding the beneficial effects of Atlantic bluefin tuna consumption. A review of the risk-benefit ratio was also conducted to evaluate the safety of its consumption, considering the current suggested limitations to this species' consumption.

7.
Crit Rev Anal Chem ; 52(4): 712-734, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33026841

RESUMEN

Metabolomics is a young field of knowledge that arises linked to other omics such as genomics, transcriptomics, and proteomics. This discipline seeks to understand the performance of metabolites, identifying, quantifying them, and thus understanding its mechanism of action. This new branch of omics science shows high potential, due to its noninvasive character and its close relation with phenotype. Several techniques have been developed to study the metabolome of biological samples, fundamentally nuclear magnetic resonance (NMR), mass spectrometry (MS) and vibrational spectrometry (VS) or a combination of several techniques. These techniques are focused to separate, detect, characterize, and quantify metabolites, as well as elucidate their structures and their function on the metabolic pathways they are involved. However, due to the complexity of the metabolome, in most cases it is necessary to apply several of these techniques to understand completely the whole scenery. This review is aimed to offer a summary of the current knowledge of these analytical techniques for metabolomics and their application to different fields as environmental, food or health sciences. Each technique shows different advantages and drawbacks depending on their technical characteristics and limitations, some factors, such as the aim of the study or the nature of the biological sample will condition the choice. Regarding their applications, NMR has been employed specially to identify new compounds and elucidate structures. The use of MS has gained popularity because of its versatility, easiness to be coupled to separation techniques and its high sensitivity. Whereas VS is widely employed for in situ studies, due to its nondestructive character. Metabolomics applications in different science fields are growing each year, due to advances in analytical techniques and combination with other omics that allow to increase the comprehension of metabolic processes. Further development of analytical tools is necessary to continue exploiting all the possibilities of metabolomics. HighlightsMetabolomics seeks to understand the performance of metabolites and its mechanism of actionDifferent metabolomics techniques have been developed and improved in the last yearsMetabolomics applications cover clinical, pharmaceuticals and food and environmental sciencesThis review is aimed to offer a summary of the current knowledge of these analytical techniques.


Asunto(s)
Metaboloma , Metabolómica , Salud Ambiental , Tecnología de Alimentos , Espectrometría de Masas/métodos , Metabolómica/métodos
8.
Food Sci Technol Int ; 17(2): 177-83, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21436232

RESUMEN

Due to the great volume of banana skin resulting from the industrialization of banana and to their high pectin content, the objectives of the present study were to evaluate the effect of the following factors: extract/sugar, pectin and citric acid on the chemical, physical and sensory qualities of the jellies obtained. A complete factorial experimental design was used (2(3)) with 3 central points to evaluate the influence of the factors on the dependent variables, testing the linear models. The chemical properties underwent few alterations and the instrumental and sensory texture attributes were mainly affected by the extract/sugar ratio and the pectin level. The brittleness, elasticity and gumminess increased with increases in the extract/ sugar ratio and pectin level. According to the sensory analysis and the purchasing intention, the best formulations were those obtained using a higher extract/sugar ratio (60/40) and lower pectin level (0.5 g/ 100), combined with the highest (20 mL) or lowest volumes of citric acid (15 mL), with scores for all the attributes in the range from 'I liked slightly' to 'I liked moderately'.


Asunto(s)
Tecnología de Alimentos/métodos , Frutas/química , Geles/química , Musa/química , Extractos Vegetales/química , Carbohidratos/análisis , Fenómenos Químicos , Ácido Cítrico/análisis , Humanos , Pectinas/análisis
9.
Foods ; 10(3)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668346

RESUMEN

The benefits of the food industry compared to other sectors are much lower, which is why producers are tempted to commit fraud. Although it is a bad practice committed with a wide variety of foods, it is worth noting the case of olive oil because it is a product of great value and with a high percentage of fraud. It is for all these reasons that the authenticity of olive oil has become a major problem for producers, consumers, and legislators. To avoid such fraud, it is necessary to develop analytical techniques to detect them. In this review, we performed a complete analysis about the available instrumentation used in olive fraud which comprised spectroscopic and spectrometric methodology and analyte separation techniques such as liquid chromatography and gas chromatography. Additionally, other methodology including protein-based biomolecular techniques and analytical approaches like metabolomic, hhyperspectral imaging and chemometrics are discussed.

10.
Food Chem ; 341(Pt 2): 128262, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33038800

RESUMEN

Given the growing tendency of consumers to choose products with natural ingredients, food industries have directed scientific research in this direction. In this regard, algae are an attractive option for the research, since they can synthesize a group of secondary metabolites, called phenolic compounds, associated with really promising properties and bioactivities. The objective of this work was to classify the major phenolic compounds, compare the effectiveness of the different extractive techniques used for their extraction, from traditional systems (like heat assisted extraction) to the most advance ones (such as ultrasound, microwave or supercritical fluid extraction); the available methods for identification and quantification; the stability of the enriched extract in phenolic compounds and the main bioactivities described for these secondary metabolites, to offer an overview of the situation to consider if it is possible and/or convenient an orientation of phenolic compounds from algae towards an industrial application.


Asunto(s)
Antiinfecciosos/farmacología , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Fenoles/farmacología , Extractos Vegetales/química , Algas Marinas/química , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Fenoles/química , Fenoles/aislamiento & purificación , Agua de Mar , Relación Estructura-Actividad
11.
Clin Nutr ; 40(11): 5430-5437, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34653819

RESUMEN

Up to half of ICU survivors, many of whom were premorbidly well, will have residual functional and/or cognitive impairment and be vulnerable to future health problems. Frailty describes vulnerability to poor resolution of homeostasis after a stressor event but it is not clear whether the vulnerability seen after ICU correlates with clinical measures of frailty. In clinical practice, the scales most commonly used in critically ill patients are based on the assessment of severity and survival. Identification and monitoring of frailty in the ICU may be an alternative or complimentary approach, particularly if it helps explain vulnerability during the recovery and rehabilitation period. The purpose of this review is to discuss the use of tools to assess frailty status in the critically ill, and consider their importance in clinical practice. Amongst these, we consider biomarkers with potential to identify patients at greater or lesser risk of developing post-ICU vulnerability.


Asunto(s)
Enfermedad Crítica , Fragilidad/diagnóstico , Gravedad del Paciente , Biomarcadores/análisis , Humanos
12.
Food Chem ; 330: 127197, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32540521

RESUMEN

Plants have been traditionally used for the treatment of different types of illness, due to biomolecules with recognised benefits. Rosaceae family is used in traditional Galician medicine. The following plants Agrimonia eupatoria, Crataegus monogyna, Filipendula ulmaria, Geum urbanum, Potentilla erecta and Rosa canina are usually found in treatments. The aim of this study is to perform an ethnobotanical review about the bioactive compounds of these plants and their different bioactivities, both studied in vitro and in vivo. The nature of the bioactive compounds is varied, highlighting the presence of different phenolic compounds, such as phenolic acids, flavonoids or tannins. Understanding the beneficial effects of the administration of the whole plant or target tissues from A. eupatoria, C. monogyna, F. ulmaria, G. urbanum, P. erecta and R. canina as well as those from their individual compounds could lead to the development of new drugs based on the use of natural ingredients.


Asunto(s)
Rosaceae/química , Desarrollo Industrial , Fenoles/química
13.
Food Funct ; 11(10): 8493-8515, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-33034610

RESUMEN

Wild edible plants (WEPs) have been consumed since ancient times. They are considered as non-domesticated plants that grow spontaneously in nature, particularly in forests and bushlands, where they can be found and collected to be incorporated into human nutrition. Increasingly, WEPs are gaining importance as they are potential sources of food due to their nutritional value, besides showing positive health effects and offer innovative applications in haute cuisine. As these autochthonous plants grow naturally in the environment, they are more suitable to adapt to different climatic conditions as well as biotic and abiotic factors. Therefore, a door has been opened for their possible cultivation as they seem to require fewer expenses than other commercially cultivated plants. Moreover, the consumers demand for new products of natural origin that are sustainable and ecologically labeled have also boosted WEPs' recovery and incorporation into the market. In addition, they are considered as promising sources of essential compounds needed not only in human diet including carbohydrates, proteins, and lipids but also of other minor compounds as phenols, vitamins, or carotenoids that have shown numerous beneficial bioactivities such as antioxidants, anti-inflammatory, or anti-tumor activity. The use of these plants rich in bioactive molecules could be beneficial from the health point of view as the human body is not always capable of producing enough defenses, for instance, preventing oxidative damage. In particular, the presence of phenolic compounds in these vegetal matrices is supposed to provide a prophylactic effect against further pathogenesis and disorders related to aging or oxidative stresses. Regarding all this information based on traditional knowledge and ethnobotanical data, different WEPs found in the Northwestern region of Spain were selected, namely, Mentha suaveolens, Glechoma hederacea, Prunus spinosa, Apium nodiflorum, Artemisia absinthium, Silybum marianum, Picris hieracioides, Portulaca oleracea, Crithmum maritimum, and the genus Amaranthus. However, even though tradition and popular knowledge are excellent tools for the exploitation of these plants, it is necessary to develop regulations in this aspect to assure safety and veracity of food products. This article aims to review the main aspects of their bioactive properties, their traditional use, and the possibility of their incorporation into the market as new functional foods, looking at innovative and healthy gastronomic applications.


Asunto(s)
Dieta , Alimentos , Salud , Valor Nutritivo , Plantas Comestibles , Antioxidantes/análisis , Carotenoides/análisis , Humanos , Legislación Alimentaria , Plantas Comestibles/química , Polifenoles/análisis , España , Vitaminas/análisis
14.
Food Funct ; 11(6): 4853-4877, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32463400

RESUMEN

Planet globalization, population growth and its consequent need to produce large amounts of food, or individual economic benefits and the prioritization of this over environment health, are factors that that have contributed to the development, in some cases, of a linear-producing modern agricultural system. In contrast to traditional and local agriculture, which was based on circular sustainability models, modern agriculture currently produces tons of waste that is accumulated in landfill, creating controversial consequences, instead of being reintroduced into the production chain with a novel purpose. However, these residues from agriculture are rich in bioactive compounds, including phenolic compounds, secondary metabolites that are found naturally in plants, which show antioxidant, anti-inflammatory, cardioprotective and anticancer capacities, among others. Although there are several suitable extractive techniques for isolating these beneficial compounds from agricultural by-products, their industrial application remains without real application value at the industrial scale. The recovery of functional phenolic compounds can be achieved, obtaining products that can be reinserted into the economy as a new raw material. The re-utilization of these compounds not only represents numerous potential applications, such as food and feed additives, functional foods, nutraceuticals, cosmeceuticals, and so forth, but also represents a favourable measure for the environment, and results in the formation of value-added products. This review summarizes all of the aspects that lead to phenolic compound recovery from agricultural wastes generated in the agro-food industries, and their potential applications within a circular and sustainable bioeconomy.


Asunto(s)
Agricultura , Antioxidantes/química , Industria de Alimentos , Polifenoles/química , Tecnología Química Verde , Humanos
15.
Animal ; 12(7): 1424-1434, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29173213

RESUMEN

Roundup is a glyphosate-based herbicide (GBH) widely used in agriculture and may cause toxic effects in non-target organisms. Model organisms, as zebrafish, and analysis of gene expression by reverse transcription-quantitative PCR (RT-qPCR) could be used to better understand the Roundup toxicity. A prerequisite for RT-qPCR is the availability of appropriate reference genes; however, they have not been described for Roundup-exposed fish. The aim of this study was to evaluate the expression stability of six reference genes (rpl8, ß-act, gapdh, b2m, ef1α, hprt1) and one expressed repetitive element (hatn10) in organs of males (brain, gill, testis) and females (ovary) of zebrafish exposed to Roundup WG at three concentrations (0.065, 0.65 and 6.5 mg N-(phosphonomethyl) glycine/l) for 7 days. Genes were ranked by geNorm, NormFinder, BestKeeper, Delta C t and RefFinder, and their best combinations were determined by geNorm and NormFinder programs. The two most stable ranked genes were specific to each organ: gill (ß-act; rpl8); brain (rpl8; ß-act); testis (ef1α; gapdh); and ovary (rpl8; hprt1). The cat transcript level was used to evaluate the effect of normalization with these reference genes. These are the first suitable reference genes described for the analysis of gene expression in organs of Roundup-exposed zebrafish, and will allow investigations of the molecular mechanisms of Roundup toxicity.


Asunto(s)
Perfilación de la Expresión Génica , Glicina/análogos & derivados , Reacción en Cadena en Tiempo Real de la Polimerasa , Pez Cebra , Animales , Femenino , Glicina/toxicidad , Herbicidas , Masculino , Estándares de Referencia , Transcripción Reversa , Pez Cebra/genética , Glifosato
16.
Life Sci ; 81(3): 198-203, 2007 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-17574275

RESUMEN

Obesity is frequently associated with consumption of high amounts of sugar and/or fat. Studies have demonstrated a high prevalence of overweight and obesity associated or not with increase rates of psychiatry disorders, in particular mood and anxiety disorders. Recent works have demonstrated an association between specific genes involved in oxidative stress metabolism and anxiety-like behavior. The aim of this study was to investigate the effect of a highly palatable diet enriched with sucrose in body fat mass composition, anxiety behavior and brain oxidative status. Twenty male Wistar rats received two different diets during four months: standard chow (SC) and highly palatable (HP). Metabolic parameters, behavioral tests and oxidative stress status were evaluated. Body fat mass, insulin sensitivity and glucose tolerance were altered in the HP group (p<0.01). The same group spends less time in light compartment and had a lower risk assessment behavior (p<0.05) but no differences were observed in the open field test habituation (p>0.05). Protein degradation, DCF and TBARS levels were not different in the hippocampus between groups; however, there were higher levels of protein degration in frontal cortex of HP groups (p<0.05), although DCF and TBARS levels don't differ from the SC group (p>0.05). In conclusion, our data suggest that the consumption of HP diet leads to an obese phenotype, increases protein oxidation in frontal cortex and appears to induce anxiety-like behavior in rats.


Asunto(s)
Ansiedad/psicología , Conducta Animal/fisiología , Dieta , Proteínas del Tejido Nervioso/metabolismo , Corteza Prefrontal/metabolismo , Animales , Composición Corporal/efectos de los fármacos , Conducta Exploratoria/efectos de los fármacos , Radicales Libres/metabolismo , Prueba de Tolerancia a la Glucosa , Peroxidación de Lípido/efectos de los fármacos , Masculino , Proteínas del Tejido Nervioso/biosíntesis , Estrés Oxidativo/fisiología , Proteínas Tirosina Quinasas/metabolismo , Ratas , Ratas Wistar , Sacarosa/farmacología , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Triptófano/metabolismo
17.
Oper Dent ; 41(4): 409-16, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26919084

RESUMEN

The properties of composite resins can be influenced by light activation, depending primarily on the performance of the curing unit. The aim of this study was to evaluate how different battery levels of a cordless light-emitting diode (LED) unit influence the properties of a nanofilled composite resin. First, the battery voltage and light intensity of the cordless LED unit were individually checked for all light-curing cycles. Then, composite resin discs were prepared and light-cured at different battery levels: high level (HL, 100%), medium level (ML, 50%), and low level (LL, 10%). The degree of conversion, diametral tensile strength, sorption, and solubility of the specimens were tested. Data were checked for homoscedasticity and submitted to one-way analysis of variance followed by Tukey honestly significant difference and Pearson correlation tests (p<0.05). The battery voltage and light intensity varied significantly among the groups (p<0.001). The LL group presented a lower degree of conversion than the HL and ML groups (p<0.001), which shower similar results (p=0.182). Lower diametral tensile strength was also verified for the LL group when compared with the HL and ML groups (p<0.001), which presented no difference (p=0.052). Positive correlation was observed between the light intensity and the parameters studied, with the exception of sorption and solubility (p<0.001). The ML and LL groups showed higher sorption than the HL group (p <0.001), but no difference was verified between the first two groups (p=0.535). No significant differences were found for solubility between the ML and LL groups (p=0.104), but the HL group presented lower values (p<0.001). The different battery levels of the cordless LED curing unit influenced all the properties of the nanofilled composite resin evaluated.


Asunto(s)
Resinas Compuestas , Luces de Curación Dental , Suministros de Energía Eléctrica , Humanos , Ensayo de Materiales , Propiedades de Superficie , Resistencia a la Tracción
18.
Arch Intern Med ; 161(10): 1313-7, 2001 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-11371260

RESUMEN

BACKGROUND: Despite concern about the impact of financial incentives on physician behavior, little is known about patients' attitudes toward these incentives. OBJECTIVES: To assess patient attitudes toward physician compensation models and to explore patient characteristics associated with these attitudes. METHODS: We mailed a survey to 2000 adult patients in a large New England health maintenance organization. We asked about their trust in their primary care physician; discomfort with compensation models of salary with withhold (salary), fee-for-service with withhold, and group capitation (capitation). RESULTS: One thousand one hundred twenty-five (56%) of the 2000 patients who responded expressed varying levels of discomfort with the proposed compensation models: 16% for salary, 25% for fee-for-service with withhold, and 53% for capitation (P<.001). Patients who knew their primary care physician was paid through capitation did not report less trust in their primary care physician but still frequently expressed discomfort (46%) with capitation. Among all respondents, those who were younger, white, had better health, had a higher income, were more educated, and who lacked a very trusting relationship with a primary care physician were more likely to report discomfort with both capitation and fee-for-service with withhold. In multivariable analyses, discomfort with capitation was more common among white patients (odds ratio, 2.6; 95% confidence interval, 1.6-4.2), patients with incomes exceeding $20 000 (odds ratio, 3.7; 95% confidence interval, 2.3-6.1), and college-educated patients (odds ratio, 2.0; 95% confidence interval, 1.4-2.7). CONCLUSIONS: Most patients were uncomfortable with 1 or more of the 3 common methods used to pay physicians. Discomfort was highest with capitation and was more likely among wealthier, well-educated, white patients. With capitation increasing nationally, patients' concerns should be considered in the design of compensation agreements.


Asunto(s)
Actitud , Capitación , Sistemas Prepagos de Salud/economía , Pacientes , Planes de Incentivos para los Médicos/estadística & datos numéricos , Relaciones Médico-Paciente , Pautas de la Práctica en Medicina/economía , Adulto , Análisis de Varianza , Capitación/estadística & datos numéricos , Planes de Aranceles por Servicios/estadística & datos numéricos , Femenino , Encuestas de Atención de la Salud , Sistemas Prepagos de Salud/estadística & datos numéricos , Humanos , Modelos Logísticos , Masculino , Massachusetts , Persona de Mediana Edad , Planes de Incentivos para los Médicos/economía , Probabilidad , Factores Socioeconómicos
19.
Braz J Biol ; 75(4): 783-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26602340

RESUMEN

The aim of this study was to characterize the local fauna of Hymenoptera parasitoids associated with Lepidoptera larvae in areas of reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP, Brazil). Lepidoptera larvae collected with entomological umbrella were kept in the laboratory until emergence of adults or their parasitoids. From those collected in the agrosilvopastoral system, emerged 267 specimens of hymenopteran parasitoids belonging to 16 genera: Braconidae, Agathidinae (Alabagrus), Braconinae (Bracon), Microgastrinae (Cotesia, Diolcogaster, Glyptapanteles, Pholetesor and Protapanteles), Orgilinae (Orgilus); Ichneumonidae, Campopleginae (Casinaria, Charops and Microcharops); Chalcididae, Chalcidinae (Brachymeria and Conura); Eulophidae, Entedoninae (Horismenus), Eulophinae (Elachertus and Euplectrus). From the Lepidoptera larvae collected in the reforestation, emerged 68 specimens of hymenopteran parasitoids, belonging to 8 genera: Chalcididae, Chalcidinae (Conura); Ichneumonidae, Pimplinae (Neotheronia), Campopleginae (Charops and Microcharops) and Braconidae, Microgastrinae (Apanteles, Diolcogaster, Distatrix, Glyptapanteles and Protapanteles). The results of this study suggest the occurrence of a wide variety of Hymenoptera parasitoids in the studied environments.


Asunto(s)
Lepidópteros/parasitología , Avispas/fisiología , Agricultura , Animales , Brasil , Ambiente , Agricultura Forestal , Interacciones Huésped-Parásitos , Larva/crecimiento & desarrollo , Larva/parasitología , Larva/fisiología , Lepidópteros/crecimiento & desarrollo , Pupa/crecimiento & desarrollo , Pupa/parasitología , Pupa/fisiología , Avispas/crecimiento & desarrollo
20.
Aust Dent J ; 60(3): 309-16, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25312697

RESUMEN

BACKGROUND: The present study analysed the effects of different occlusal loading on premolars displaying various non-carious cervical lesions morphologies, restored (or not) with composites, by 3D finite element analysis. METHODS: A three-dimensional digital model of a maxillary premolar was generated using CAD software. Three non-carious cervical lesions morphological types were simulated: wedged-shaped, saucer and mixed. All virtual models underwent three loading types (100 N): vertical, buccal and palatal loading. The simulated non-carious cervical lesions morphologies were analysed with and without restorations to consider specific regions, such as the occlusal and gingival walls as well as the depth of the lesions. Data summarizing the stress distribution were obtained in MPa using Maximum Principal Stress. RESULTS: Palatal loads were responsible for providing the highest values of accumulated tensile stress on the buccal wall; 27.66 MPa and 25.76 MPa for mixed and wedged-shaped morphologies, respectively. The highest tensile values found on non-carious cervical lesions morphologies restored with composite resin were 5.9 MPa in the mixed morphology, similar to those found on sound models despite their morphologies and occlusal loading. CONCLUSIONS: The various non-carious cervical lesions morphologies had little effect on stress distribution patterns, whereas the loading type and presence of composite restorations influenced the biomechanical behaviour of the maxillary premolars.


Asunto(s)
Fuerza de la Mordida , Resinas Compuestas/química , Restauración Dental Permanente/métodos , Análisis de Elementos Finitos , Imagenología Tridimensional/métodos , Cuello del Diente/fisiopatología , Desgaste de los Dientes/fisiopatología , Diente Premolar/fisiopatología , Fenómenos Biomecánicos , Análisis del Estrés Dental/métodos , Módulo de Elasticidad , Humanos , Maxilar , Modelos Anatómicos , Modelos Biológicos , Estrés Mecánico , Resistencia a la Tracción , Interfaz Usuario-Computador
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