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1.
Food Chem ; 295: 156-164, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174744

RESUMO

During ageing, wood adsorbs volatile compounds from beverages. However, chemical interactions involved in sorption still remain unclear, as well as wood capacity to transfer such compounds to subsequent matrices when reused. Therefore, extractions were conducted from used wood manipulating variables such as ethanol concentration, contact temperature and pH, in order to determine their effect in the interaction and consequent recovery of wine volatiles from wood. Mathematical models were outlined, which demonstrated an exclusive effect of ethanol concentration on the extraction of wine volatiles adsorbed in wood, more prominent for compounds of higher hydrophobicity. Thus adsorption of wine volatiles was shown to be based on hydrophobic interactions. Recovery of wood extractives was also modeled, confirming the known positive effect of ethanol and temperature on the overall extraction of characteristic wood compounds. When reused, wood transferred wine compounds to hydroalcoholic matrices, demonstrating its impact and potential as a vector for aroma transference.


Assuntos
Quercus/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Madeira/química , Adsorção , Etanol/química , Concentração de Íons de Hidrogênio , Temperatura Ambiente , Fatores de Tempo
2.
Eur J Oral Sci ; 126(2): 146-158, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29380895

RESUMO

This study evaluated the effect of dentin pretreatment with the polyphenols quercetin and resveratrol on the resin-dentin microtensile bonding strength (µTBS) and collagen fibrils stability of the adhesive interface. Different concentrations (100, 250, 500, or 1,000 µg ml-1 ) of quercetin or resveratrol, or a mixture of quercetin and resveratrol (3:1, 1:1, 1:3; vol:vol), as well as distilled water or 2% chlorhexidine digluconate, were applied to etched dentin. Then, a two-step etch-and-rinse adhesive was applied followed by composite restoration. Measurements of resin-dentin µTBS were made after 1 and 120 d. The stability of collagen fibrils in the hybrid layer was evaluated using transmission electron microscopy. The Student's t-test and two-way factorial anova with Tukey's test were used to analyze the effects of dentin pretreatment and storage time on µTBS values. Comparisons between µTBS measurements made on 1 and 120 d showed that resveratrol had the best performance, with significantly higher µTBS values after 120 d for all concentrations of resveratrol tested. Quercetin pretreatment resulted in a significant rise of µTBS when used at concentrations of 100 and 500 µg ml-1 . Quercetin + resveratrol at the ratio of 1:1 performed better than when used at ratios of either 3:1 or 1:3. Resveratrol might represent a potential approach to achieve desirable bonding stability and reduce the frequent replacement of composite restorations.

3.
Public Health Nutr ; 21(3): 543-557, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29173214

RESUMO

OBJECTIVE: The present study aimed to (i) assess the appetitive drives evoked by the visual cues of ultra-processed food and drink products and (ii) investigate whether text warnings reduce appetitive drives and consumers' reported intentions to eat or drink ultra-processed products. DESIGN: In Study I, a well-established psychometric tool was applied to estimate the appetitive drives associated with ultra-processed products using sixty-four image representations. Sixteen product types with four exemplars of a given product were included. Pictures from the International Affective Picture System (IAPS) served as controls. The two exemplars of each product type rated as more appetitive were selected for investigation in the second study. Study II assessed the impact of textual warnings on the appetitive drive towards these thirty-two exemplars. Each participant was exposed to two picture exemplars of the same product type preceded by a text warning or a control text. After viewing each displayed picture, the participants reported their emotional reactions and their intention to consume the product. SETTING: Controlled classroom experiments SUBJECTS: Undergraduate students (Study I: n 215, 135 women; Study II: n 98, 52 women). RESULTS: In Study I, the pictures of ultra-processed products prompted an appetitive motivation associated with the products' nutritional content. In Study II, text warnings were effective in reducing the intention to consume and the appetitive drive evoked by ultra-processed products. CONCLUSIONS: This research provides initial evidence favouring the use of text warnings as a public policy tool to curb the powerful influence of highly appetitive ultra-processed food cues.

4.
World J Nucl Med ; 16(1): 3-7, 2017 Jan-Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28217012

RESUMO

The 68Ga-prostate-specific membrane antigen ( 68Ga-PSMA) has been recently developed to be used, as a ligand, in positron emission tomography/computed tomography (PET/CT) prostate cancer imaging, to detect prostate disease. The main objective of this review was to collect data and findings from other studies and articles to assess, theoretically, if 68GA-PSMA PET/CT is a more appropriate prostate cancer diagnostic technique in comparison with others available such as CT, 18F-fluoro-2-deoxyglucose PET/CT, or 18F-fluoromethylcholine ( 18F-choline) PET/CT. For that purpose, PubMed, the online scientific articles' database, was consulted where the keywords "PSMA" and "PET" were used to find relevant articles. The clinicaltrials.gov, clinical trials' database, was also consulted where the keywords "68Ga-PSMA" and "prostate" were used to search clinical trials. Based on the reviewed scientific literature, several studies were conducted to assess and compare the 68Ga-PSMA PET/CT detection rate in prostate cancer with other available techniques. One of those studies, conducted by Giesel et al., concluded, within study sample, that 75% of patients with lymph nodes detected by 68Ga-PSMA PET/CT would have not been identified using other conventional morphological criteria based techniques. In Eiber et al.'s study, 68Ga-PSMA PET detected prostatic disease findings in 67% of patients with prostate-specific antigen levels <1 ng/mL, when compared with choline-based PET that presented detection rates between 19% and 36%. In Bluemel et al.'s study, 68Ga-PSMA identified positive prostatic disease in 43.8% of the patients with negative findings in F-choline PET/CT. Findings from this review demonstrate that 68Ga-PSMA PET/C is more effective in detecting metastases, lymph nodes, and recurrent prostate cancer when compared to 18F-choline-based PET/CT and CT. 68Ga-PSMA PET/CT presents also more imaging contrast and can be more cost-effective. 68Ga-PSMA has already been subjected to first-in-human trials, and it is now being tested in Phase II and III trials.

5.
J Environ Sci (China) ; 51: 191-201, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28115130

RESUMO

The antibacterial potential of silver nanoparticles (AgNPs) resulted in their increasing incorporation into consumer, industrial and biomedical products. Therefore, human and environmental exposure to AgNPs (either as an engineered product or a contaminant) supports the emergent research on the features conferring them different toxicity profiles. In this study, 30nm AgNPs coated with citrate or poly(ethylene glycol) (PEG) were used to assess the influence of coating on the effects produced on a human hepatoma cell line (HepG2), namely in terms of viability, apoptosis, apoptotic related genes, cell cycle and cyclins gene expression. Both types of coated AgNPs decreased cell proliferation and viability with a similar toxicity profile. At the concentrations used (11 and 5µg/mL corresponding to IC50 and ~IC10 levels, respectively) the amount of cells undergoing apoptosis was not significant and the apoptotic related genes BCL2 (anti-apoptotic gene) and BAX (pro-apoptotic gene) were both downregulated. Moreover, both AgNPs affected HepG2 cell cycle progression at the higher concentration (11µg/mL) by increasing the percentage of cells in S (synthesis phase) and G2 (Gap 2 phase) phases. Considering the cell-cycle related genes, the expression of cyclin B1 and cyclin E1 genes were decreased. Thus, this work has shown that citrate- and PEG-coated AgNPs impact on HepG2 apoptotic gene expression, cell cycle dynamics and cyclin regulation in a similar way. More research is needed to determine the properties that confer AgNPs at lower toxicity, since their use has proved helpful in several industrial and biomedical contexts.


Assuntos
Antibacterianos/toxicidade , Ácido Cítrico/toxicidade , Substâncias Perigosas/toxicidade , Nanopartículas Metálicas/toxicidade , Polietilenoglicóis/toxicidade , Prata/toxicidade , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas
6.
Appl Radiat Isot ; 118: 221-227, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27684453

RESUMO

Cigarette smoking is a serious public health problem. According to data from the World Health Organization, it is estimated that currently more than 1.2 billion people worldwide do tobacco use and that smoking-related diseases are responsible for about 6 million deaths each. With attention to this, it is necessary to seek preventive and prognostic of trying to reduce these numbers and alert the public in general about the danger and the harm caused by its use. Thus, the objective of the research work undertaken was to evaluate and compare the chemical composition of collected saliva samples of smokers and nonsmokers by X-ray Fluorescence analyses. 32 individuals were selected, 16 of which used cigarette on a daily basis and the other 16 had never smoked. Saliva was collected with the help of a (sterile) disposable Pasteur pipette and samples sent to the Applied Nuclear Physics Laboratory at UNISO (LAFINAU), where analyzes were carried out. Individuals who agreed to participate in the study answered a questionnaire to define their profile of inclusion and signed an informed consent form (CEP Protocol no. 831.753 of 09/10/2014). The results clearly showed that there are differences in the concentrations of chemical elements in the saliva of smokers and non-smokers. The biggest discrepancies were found at concentrations of the chemical elements Sulfur, Phosphorus, Chlorine and Potassium, and smaller differences in the concentration of the elements Calcium, Manganese, Iron, Copper, Titanium, Vanadium and Nickel. In only one saliva sample, and in quite low amounts, arsenic was detected. The results indicate that smoking produces more significant changes in the saliva of women than in men, increasing the concentration of some elements in the saliva of female smokers, much more than in the male smokers. The cigarette usage time also appears to exert a greater influence on the composition of the saliva of women than in men, indicating that the damage caused by cigarette use may in fact be higher in women than in men.


Assuntos
Saliva/química , Fumar/metabolismo , Espectrometria por Raios X/métodos , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Caracteres Sexuais
7.
Behav Brain Res ; 302: 252-62, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26802729

RESUMO

Threatening cues and surrounding contexts trigger specific defensive response patterns. Potential threat evokes attentive immobility; attack evokes flight when escape is available and immobility when escape is blocked. Tonic immobility installs when threat is overwhelming and life-risky. In humans, reduced body sway characterizes attentive and tonic immobility, the former with bradycardia, and the later with expressive tachycardia. Here, we investigate human defensive strategies in the presence or absence of an escape route. We employed pictures depicting a man carrying a gun and worked with participants exposed to urban violence. In pictures simulating more possibility of escape, the gun was directed away from the observer; in those simulating higher risk and less chance of escape, the gun was directed toward the observer. Matched control pictures depicted similar layouts, but a non-lethal object substituted the gun. Posturographic and electrocardiographic recordings were collected. Amplitude of sway and heart rate were higher for gun directed-away and lower for gun direct-toward. Compared to their respective matched controls, there was a general increase in the amplitude of sway for the gun directed-away pictures; and a reduction in back-and-forth sway and in heart rate for gun directed-toward pictures. Taken together, those measures suggest that, when exposed to threat invading their margin of safety in a context indicating possible escape route, humans, as non-human species, engage in active escape, resembling the flight stage of the defensive cascade. When facing threat indicating less possibility of escape, humans present an immobile response with bradycardia.


Assuntos
Sinais (Psicologia) , Mecanismos de Defesa , Reação de Fuga/fisiologia , Percepção Visual/fisiologia , Adulto , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Fixação Ocular/fisiologia , Reação de Congelamento Cataléptica/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Movimento , Estimulação Luminosa , Estatísticas não Paramétricas , Estudantes , Universidades , Adulto Jovem
8.
J Biomed Mater Res B Appl Biomater ; 104(7): 1483-94, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26148945

RESUMO

Tissue engineering plays a significant role both in the re-establishment of functions and regeneration of organic tissues. Success in manufacturing projects for biological scaffolds, for the purpose of tissue regeneration, is conditioned by the selection of parameters such as the biomaterial, the device architecture, and the specificities of the cells making up the organic tissue to create, in vivo, a microenvironment that preserves and further enhances the proliferation of a specific cell phenotype. To support this approach, we have screened scientific publications that show biomedical applications of scaffolds, biomechanical, morphological, biochemical, and hemodynamic characteristics of the target organic tissues, and the possible interactions between different cell matrices and biological scaffolds. This review article provides an overview on the biomedical application of scaffolds and on the characteristics of the (bio)materials commonly used for manufacturing these biological devices used in tissue engineering, taking into consideration the cellular specificity of the target tissue. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1483-1494, 2016.


Assuntos
Proliferação de Células , Matriz Extracelular/química , Regeneração , Tecidos Suporte , Animais , Humanos
9.
Front Genet ; 6: 216, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26175750

RESUMO

The systematic study of genotoxicity in plants induced by contaminants and other stress agents has been hindered to date by the lack of reliable and robust biomarkers. The comet assay is a versatile and sensitive method for the evaluation of DNA damages and DNA repair capacity at single-cell level. Due to its simplicity and sensitivity, and the small number of cells required to obtain robust results, the use of plant comet assay has drastically increased in the last decade. For years its use was restricted to a few model species, e.g., Allium cepa, Nicotiana tabacum, Vicia faba, or Arabidopsis thaliana but this number largely increased in the last years. Plant comet assay has been used to study the genotoxic impact of radiation, chemicals including pesticides, phytocompounds, heavy metals, nanoparticles or contaminated complex matrices. Here we will review the most recent data on the use of this technique as a standard approach for studying the genotoxic effects of different stress conditions on plants. Also, we will discuss the integration of information provided by the comet assay with other DNA-damage indicators, and with cellular responses including oxidative stress, cell division or cell death. Finally, we will focus on putative relations between transcripts related with DNA damage pathways, DNA replication and repair, oxidative stress and cell cycle progression that have been identified in plant cells with comet assays demonstrating DNA damage.

10.
J Pharm Sci ; 104(7): 2241-54, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25952004

RESUMO

Development and optimization of a hydrogel with impregnated silver sulfadiazine was pursued, for antimicrobial topical applications. The selected hydrogel exhibited a homogeneous appearance, with whitish colloration and devoid of any fractures or cracks. The content in impregnated silver sulfadiazine was within established limits (1%, w/w) with a standard deviation of up to 1.28%. The hydrogel presented a good characteristic in relation to release of the active antimicrobial principle, verified through swelling tests and antimicrobial activity. The swelling tests indicated a higher increase in weight during the first 6 h of contact with a moist environment, with a maximum value of 266.00 ± 0.81, and with maintenance of the original shape of the hydrogel. The impregnated silver sulfadiazine presented antimicrobial activity, as expected, indicating a prolonged release of the drug. The infrared spectra of the hydrogel with impregnated silver sulfadiazine indicated that the drug did not engage in any bonds with the polymeric matrix, which otherwise could have reduced its antimicrobial activity. The mechanical resistance tests produced good results, indicating that the hydrogels may be utilized in different locations of the human body with skin lesions.


Assuntos
Antibacterianos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Sulfadiazina de Prata/química , Prata/química , Antibacterianos/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Prata/farmacologia , Sulfadiazina de Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos
11.
Front Psychol ; 6: 16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25674068

RESUMO

It is assumed that social bonds in humans have consequences for virtually all aspects of behavior. Social touch-based contact, particularly hand caressing, plays an important role in social bonding. Pre-programmed neural circuits likely support actions (or predispositions to act) toward caressing contacts. We searched for pre-set motor substrates toward caressing by exposing volunteers to bonding cues and having them gently stroke a very soft cloth, a caress-like movement. The bonding cues were pictures with interacting dyads and the control pictures presented non-interacting dyads. We focused on the readiness potential, an electroencephalographic marker of motor preparation that precedes movement execution. The amplitude of the readiness potential preceding the grasping of pleasant emotional-laden stimuli was previously shown to be reduced compared with neutral ones. Fingers flexor electromyography measured action output. The rationale here is that stroking the soft cloth when previously exposed to bonding cues, a compatible context, would result in smaller amplitudes of readiness potentials, as compared to the context with no such cues. Exposure to the bonding pictures increased subjective feelings of sociability and decreased feelings of isolation. Participants who more frequently engage in mutual caress/groom a "significant other" in daily life initiated the motor preparation earlier, reinforcing the caress-like nature of the task. As hypothesized, readiness potentials preceding the caressing of the soft cloth were significantly reduced under exposure to bonding as compared to control pictures. Furthermore, an increased fingers flexor electromyographic activity was identified under exposure to the former as compared to the latter pictures. The facilitatory effects are likely due to the recruitment of pre-set cortical motor repertoires related to caress-like movements, emphasizing the distinctiveness of neural signatures for caress-like movements.

12.
Front Hum Neurosci ; 9: 715, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26834610

RESUMO

OBJECTIVE: To investigate whether a sensorimotor deficit of the upper limb following a brachial plexus injury (BPI) affects the upright balance. DESIGN: Eleven patients with a unilateral BPI and 11 healthy subjects were recruited. The balance assessment included the Berg Balance Scale (BBS), the number of feet touches on the ground while performing a 60 s single-leg stance and posturographic assessment (eyes open and feet placed hip-width apart during a single 60 s trial). The body weight distribution (BWD) between the legs was estimated from the center of pressure (COP) lateral position. The COP variability was quantified in the anterior-posterior and lateral directions. RESULTS: BPI patients presented lower BBS scores (p = 0.048) and a higher frequency of feet touches during the single-leg stance (p = 0.042) compared with those of the healthy subjects. An asymmetric BWD toward the side opposite the affected arm was shown by 73% of BPI patients. Finally, higher COP variability was observed in BPI patients compared with healthy subjects for anterior-posterior (p = 0.020), but not for lateral direction (p = 0.818). CONCLUSIONS: This study demonstrates that upper limb sensorimotor deficits following BPI affect body balance, serving as a warning for the clinical community about the need to prevent and treat the secondary outcomes of this condition.

13.
Postgrad Med ; 126(4): 171-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25141254

RESUMO

As the population ages and diabetes mellitus increases in prevalence, the incidence of diabetic nephropathy (DN) is becoming a disease of older people (aged ≥ 75 years). As the epidemiology of diabetes mellitus and DN shifts toward this patient population, the pathogenesis of DN in old age is changing: the pathologic findings suggest ischemia and hypertension, and the classic Kimmelstiel-Wilson lesions may be absent. The demographic shift in the epidemiology and the associated changes in pathology because of aging and atherosclerosis will have a significant impact on various aspects related to the disease in old age. This article reviews the authors' current understanding of DN and its implications on clinical management relevant to current guidelines.


Assuntos
Nefropatias Diabéticas/terapia , Guias de Prática Clínica como Assunto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/fisiopatologia , Dislipidemias/terapia , Idoso Fragilizado , Hemoglobina A Glicada , Humanos , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/terapia
14.
Curr Pharm Biotechnol ; 15(2): 182-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25135342

RESUMO

The goal of the research work entertained herein was the development and characterization of a poly-(vinyl alcohol) (PVA) hydrogel cross-linked with glutaraldehyde and impregnated with 0.2% (w/w) nitrofurazone (NTZ), for topical applications. To verify the active principle release capability, one has determined (i) swelling profile, (ii) in vitro release of NTZ via UV-VIS spectrophotometry, and (iii) antimicrobial activity via exposure to the hydrogel of ATCC strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The optimized hydrogel was further characterized via scanning electron microscopy (SEM), infrared spectroscopy with Fourier transform, moisture content determinations and thermal analyses via thermal gravimetry (TGA). Swelling tests revealed a mass increase from 100±5% up to 350±11%. Incorporated NTZ displayed bactericidal activity, as expected, being released in a linearly controlled fashion above 6 µg/mL during experiment timeframes of 14 h. SEM analyses allowed verification of a homogeneous surface morphology, while infrared spectra showed that NTZ did not bind strongly to the cross-linked polymer. Furthermore, results from thermal analyses suggested a loss of thermal stability arising from incorporation of NTZ in the hydrogel. The optimized hydrogel exhibited characteristics with high potential for (antimicrobial) treatment of skin lesions.


Assuntos
Anti-Infecciosos/química , Hidrogéis/química , Nitrofurazona/química , Administração Tópica , Liberação Controlada de Fármacos , Microscopia Eletrônica de Varredura , Espectrofotometria Infravermelho , Termogravimetria
15.
PLoS One ; 8(8): e72117, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23977223

RESUMO

OBJECTIVE: The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control. METHODS: Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs' manipulation, and quantified judgments of warnings' emotional strength and efficacy against smoking. FINDINGS: Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants' judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking. CONCLUSIONS: Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change.


Assuntos
Motivação , Rotulagem de Produtos , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Produtos do Tabaco , Adolescente , Adulto , Nível de Alerta , Terapia Aversiva , Feminino , Humanos , Masculino , Estimulação Luminosa , Prevenção do Hábito de Fumar , Adulto Jovem
16.
Behav Brain Res ; 236(1): 166-74, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22964139

RESUMO

Spatiotemporal discontinuity of visual input is a common occurrence in daily life. For example, when a walking person disappears temporarily behind a wall, observers have a clear sense of his physical presence despite the absence of any visual information (movement permanence). To investigate the neural substrates of biological motion permanence, we recorded scalp EEG activity of sixteen subjects while they passively observed either biological or scrambled motion disappearing behind an occluder and reappearing. The moment of the occluder's appearance was either fixed or randomized. The statistical comparison between the biological and scrambled motion ERP waveforms revealed a modulation of activity in centro-parietal and right occipito-temporal regions during the occlusion phase when the biological motion disappearance was time-locked, possibly reflecting the recall of sensorimotor representations. These representations might allow the prediction of moving organisms in occlusion conditions. When the appearance of the occluder was unpredictable there was no difference between biological and scrambled motion either before or during occlusion, indicating that temporal prediction is relevant to the processing of biological motion permanence.


Assuntos
Fenômenos Eletrofisiológicos/fisiologia , Movimento (Física) , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Córtex Cerebral/fisiologia , Análise por Conglomerados , Interpretação Estatística de Dados , Eletrodos Implantados , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Rede Nervosa/fisiologia , Estimulação Luminosa , Adulto Jovem
17.
Behav Res Methods ; 44(4): 1115-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22477437

RESUMO

Brain event-related potentials are a useful tool for investigating visual processing and action planning. This technique requires extremely accurate synchronization of stimulus delivery with recordings. The precision of the onset time of visual stimulus delivery is a major challenge when attempting to use real, three-dimensional objects as stimuli. Here, we present an innovative device, the "box for interaction with objects" (BIO), that is designed to synchronize the presentation of objects with electroencephalographic (EEG) recordings. To reach the required resolution of stimulus-onset timing, the BIO system features an interface with reflective glass and light-emitting diodes (LEDs). When the LEDs inside the BIO are turned on, the object inside becomes visible, and a synchronizing pulse is sent to the recording systems. The BIO was tested in a motivational study that focused on visual and motor event-related potentials. EEG signals were recorded during the presentation of an emotion-laden object that could be grasped and brought close to the participant's chest. BIO successfully synchronized the appearance of a three-dimensional object with EEG recordings, which would allow for an analysis of visual and motor event-related potentials in the same experiment. The BIO device, through a high-quality psychophysiological approach, offers a new perspective for the study of the motivational factors that drive actions toward relevant stimuli.


Assuntos
Ciências do Comportamento/instrumentação , Eletroencefalografia/métodos , Potencial Evocado Motor/fisiologia , Potenciais Evocados Visuais/fisiologia , Movimento , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Eletroencefalografia/instrumentação , Emoções , Desenho de Equipamento , Feminino , Humanos , Masculino , Motivação
18.
Phytochemistry ; 74: 196-205, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22071134

RESUMO

The volatile composition of white Agudelo, Blancolexitimo, Godello and red Serradelo cultivars (NW Spain) harvested at two different stages of ripening have been evaluated. C(6)-compounds, alcohols, volatile fatty acids, monoterpenes, C(13)-norisoprenoids, volatile phenols and carbonyl compounds were identified and quantified in free and glycosidically bound forms by gas chromatography-mass spectrometry (GC-MS). The total volatile concentration showed a significant increase between the two ripening stages studied for all cultivars. The free volatile composition increased during maturity for Godello and Serradelo cultivars; however the glycosidically bound concentration increases for all cultivars with exception of B. lexitimo. Free C(6)-compounds ((E)-2-hexanal, 1-hexanol and (E)-2-hexen-1-ol) and bound alcohols (benzyl alcohol and 2-phenylethanol) showed the highest concentrations of volatile compounds for all grape cultivars in the two dates studied. Godello cultivar showed the highest change of volatile concentration between two ripening dates because of the high value of free C(6)-compounds. B. lexitimo was the most terpene-rich cultivar at the last ripening stage due to linalool; however C(13)-norisoprenoids in free form were detected in low concentrations for all cultivars but not in Godello and B. lexitimo cultivars at the last ripening stage. Free hexanoic acid increased during ripening in all cultivars. The evolution of volatiles during ripening of grape juice from the cultivars studied was not proportional to the changes in sugar content, which shows that the technological and aromatic maturities did not occur at the same time in these cultivars. The results also showed the cultivar * ripening date interaction for all, free and bound, groups of compounds.


Assuntos
Frutas/química , Vitis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Odorantes , Especificidade da Espécie , Vitis/classificação
19.
Biol Psychol ; 88(1): 13-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21693167

RESUMO

Tonic immobility, characterized by profound motor inhibition, is elicited under inescapable threat in many species. To fully support the existence of tonic immobility in humans, our aim was to elicit this reaction in a laboratory setting and measure it objectively. To mimic exposure to life-threatening events in the lab, trauma-exposed participants with PTSD (n=18) and without PTSD (n=15) listened to the script of their autobiographical trauma. Posturography and electrocardiography were employed. Reports of script-induced immobility were associated with restricted area of body sway and were correlated with accelerated heart rate and diminished heart rate variability, implying that tonic immobility is preserved in humans as an involuntary defensive strategy. Immobility reports seemed more evident in PTSD, suggesting that, in some patients, tonic immobility may be elicited during re-experiencing episodes in daily life. This study provided a measure of tonic immobility, a peritraumatic reaction for which cumulative clinical evidence had linked to the severity of PTSD.


Assuntos
Resposta de Imobilidade Tônica/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Estimulação Acústica , Adulto , Eletrocardiografia/métodos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Psicometria
20.
Int J Food Microbiol ; 143(3): 173-82, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20828848

RESUMO

Sixteen different strains of Saccharomyces cerevisiae and Saccharomyces bayanus were evaluated in the production of raspberry fruit wine. Raspberry juice sugar concentrations were adjusted to 16° Brix with a sucrose solution, and batch fermentations were performed at 22 °C. Various kinetic parameters, such as the conversion factors of the substrates into ethanol (Y(p/s)), biomass (Y(x/s)), glycerol (Y(g/s)) and acetic acid (Y(ac/s)), the volumetric productivity of ethanol (Q(p)), the biomass productivity (P(x)), and the fermentation efficiency (E(f)) were calculated. Volatile compounds (alcohols, ethyl esters, acetates of higher alcohols and volatile fatty acids) were determined by gas chromatography (GC-FID). The highest values for the E(f), Y(p/s), Y(g/s), and Y(x/s) parameters were obtained when strains commonly used in the fuel ethanol industry (S. cerevisiae PE-2, BG, SA, CAT-1, and VR-1) were used to ferment raspberry juice. S. cerevisiae strain UFLA FW 15, isolated from fruit, displayed similar results. Twenty-one volatile compounds were identified in raspberry wines. The highest concentrations of total volatile compounds were found in wines produced with S. cerevisiae strains UFLA FW 15 (87,435 µg/L), CAT-1 (80,317.01 µg/L), VR-1 (67,573.99 µg/L) and S. bayanus CBS 1505 (71,660.32 µg/L). The highest concentrations of ethyl esters were 454.33 µg/L, 440.33 µg/L and 438 µg/L for S. cerevisiae strains UFLA FW 15, VR-1 and BG, respectively. Similar to concentrations of ethyl esters, the highest concentrations of acetates (1927.67 µg/L) and higher alcohols (83,996.33 µg/L) were produced in raspberry wine from S. cerevisiae UFLA FW 15. The maximum concentration of volatile fatty acids was found in raspberry wine produced by S. cerevisiae strain VR-1. We conclude that S. cerevisiae strain UFLA FW 15 fermented raspberry juice and produced a fruit wine with low concentrations of acids and high concentrations of acetates, higher alcohols and ethyl esters.


Assuntos
Bebidas/microbiologia , Rosaceae/metabolismo , Saccharomyces/classificação , Saccharomyces/metabolismo , Bebidas/análise , Carboidratos/química , Etanol/química , Fermentação/fisiologia , Especificidade da Espécie , Compostos Orgânicos Voláteis/química
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