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1.
PLoS One ; 19(3): e0289664, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38442107

RESUMO

INTRODUCTION: Traumatic event exposure is a risk factor for the development and maintenance of psychopathology. Social-affective responses to trauma exposure (e.g. shame, guilt, revenge, social alienation) could moderate this relationship, but little is known about their relevance for different types of psychopathology. Moreover, the interplay of different social-affective responses to trauma exposure in predicting psychopathology is poorly understood. METHODS: In a sample of N = 1321 trauma-exposed German soldiers, we examined cross-sectional associations of trauma-related social alienation, revenge, guilt and shame with depressive disorder, alcohol use disorder, posttraumatic stress disorder and dimensional measures of depression and anxiety. Latent class analysis was conducted to identify possible patterns of social-affective responses to trauma exposure, and their relation to psychopathology. RESULTS: All social-affective responses to trauma exposure predicted current posttraumatic stress disorder, depressive disorder, alcohol use disorder and higher depressive and anxiety symptoms. Three latent classes fitted the data best, reflecting groups with (1) low, (2) moderate and (3) high risk for social-affective responses to trauma exposure. The low-risk group demonstrated the lowest expressions on all psychopathology measures. CONCLUSIONS: Trauma-related social alienation, shame, guilt, and revenge are characteristic of individuals with posttraumatic stress disorder, depressive disorder, alcohol use disorder, and with higher anxiety and depressive symptoms. There was little evidence for distinctive patterns of social-affective responses to trauma exposure despite variation in the overall proneness to show social-affective responses. Social-affective responses to trauma exposure could represent promising treatment targets for both cognitive and emotion-focused interventions.


Assuntos
Alcoolismo , Humanos , Estudos Transversais , Ansiedade , Culpa , Vergonha
2.
Psychol Serv ; 20(1): 84-93, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34968122

RESUMO

Social factors play a crucial role in moderating the impact of severe stressful events on mental health. Exposure to harassment, hence to unwanted negative behavior that is intended to cause harm and/or is perceived as harmful and hostile, is a social factor thought to have particularly strong negative effects on mental health, including depressive symptoms and suicidal behavior. However, little is known about mediating mechanisms. Using data of N = 1,483 participants 12 months following military deployment, the hypothesis was examined that the cross-sectional association of perceived harassment with depressive symptoms and risk for suicidal behavior (suicide ideation and plans) is partially mediated by increased perceived mental health stigma and nondisclosure. Mediation analyses were performed using path analysis. Harassment was associated with depressive symptoms and risk for suicidal behavior. When investigated separately, both nondisclosure and perceived stigma partially mediated the association of harassment with depressive symptoms and with suicidal behavior. When considered simultaneously, both nondisclosure and, to a lesser extent, perceived stigma partially mediated the association of harassment with depressive symptoms, but only nondisclosure mediated the association of harassment with suicidal behavior. These results are consistent with the assumption that nondisclosure and perceived mental health stigma following harassment contribute to depressive symptoms and risk for suicidal behavior, whereby nondisclosure is more relevant compared to perceived stigma. Nondisclosure could lead to adverse outcomes by increasing distress, limiting social support, and inhibiting help-seeking. Interventions that increase disclosure might be a promising target for early interventions following harassment. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Depressão , Ideação Suicida , Humanos , Depressão/psicologia , Estudos Transversais , Saúde Mental , Confidencialidade , Estigma Social
3.
BMC Psychiatry ; 22(1): 736, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443716

RESUMO

BACKGROUND: After stressful event exposure, higher perceived social support is a well-established correlate of decreased risk for psychological symptoms, including depressive, anxiety and posttraumatic stress (PTS) symptoms. However, longitudinal data on the direction of this association and the stability of perceived social support are scarce and have yielded mixed results, with a particular lack of prospective studies. We aimed to investigate changes in perceived social support and bidirectional associations between perceived social support and psychological symptoms in a prospective, longitudinal study. METHODS: A sample of German soldiers was assessed before and after deployment to Afghanistan. Group-based trajectory modelling was used to investigate the stability of perceived social support and to identify possible distinguishable trajectories of perceived social support. Bidirectional associations between perceived social support (general and workplace) and psychological symptoms (depressive, anxiety and PTS) were examined using gamma regressions. RESULTS: Average levels of perceived general social support did not change, while perceived workplace social support increased slightly (t(344) = 5.51, p < .001). There were no distinguishable trajectories of perceived social support. Higher perceived general (Mean ratio (MR) = 0.84, 95% CI = [0.74, 0.95]) and workplace social support (MR = 0.82, 95% CI = [0.72, 0.92]) predicted lower depressive symptoms, but not anxiety or PTS symptoms. Only higher PTS (MR = 0.95, 95% CI = [0.91, 0.99]) and higher depressive symptoms (MR = 0.96, 95% CI = [0.93, 0.99]) predicted lower perceived general social support. CONCLUSIONS: Perceived social support can remain relatively stable under exposure to environmental stressors such as military deployment. Higher perceived social support could protect against depressive symptoms via a stress-buffering mechanism, while support may need to be more tailored to individual needs for a protection against PTS symptoms. Individuals with elevated depressive and PTS symptoms might have impaired abilities or opportunities to access social support after stressful event exposure. Future studies could investigate distressing social emotions and associated maladaptive social cognitions as possible mechanisms in the association between symptoms and lower perceived social support. Especially with respect to PTS symptoms, future studies could focus on conditions that enable individuals to benefit from social support.


Assuntos
Ansiedade , Apoio Social , Humanos , Estudos Prospectivos , Estudos Longitudinais , Transtornos de Ansiedade
4.
Food Chem X ; 12: 100171, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34901827

RESUMO

Orange thyme (Thymus fragrantissimus) is becoming widely used in food as a condiment and herbal tea, nevertheless its chemical composition and potential bioactivities are largely unknown. Thus the objective of this work is to obtain a detailed phytochemical profile of T. fragrantissimus by exhaustive ethanolic extraction and by aqueous decoction mimicking its consumption. Extracts showed high content in rosmarinic acid, luteolin-O-hexuronide and eriodictyol-O-hexuronide; these were the main phenolic compounds present in orange thyme accounting for 85% of the total phenolic compounds. Orange thyme extracts presented high scavenging activity against nitric oxide and superoxide radicals. Both extracts presented significant inhibitory effect of tyrosinase activity and moderate anti-acetylcholinesterase activity. Both extracts showed a good in vitro anti-inflammatory activity and a weak anti-proliferative/cytotoxic activity against Caco-2 and HepG2 cell lines supporting its safe use. Orange thyme is a very good source of bioactive compounds with potential use in different food and nutraceutical industries.

5.
BMC Psychol ; 9(1): 198, 2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34924023

RESUMO

BACKGROUND AND OBJECTIVES: Disorder-specific forms of Repetitive Negative Thinking (RNT) are associated with multiple diagnostic categories, indicating a transdiagnostic nature. Few studies examined content-independent RNT processes across groups of diagnosed mental disorders. Moreover, theory describes RNT processes as critically involved in the etiology of mental disorders, empirical evidence however is scarce. We first tested the transdiagnostic nature by examining levels of RNT across groups of internalizing and externalizing mental disorders compared to healthy individuals and explored RNT levels in a comorbid disorder-group. Second, we examined whether RNT predicts incident psychopathology. METHODS: In a sample of German soldiers (n = 425) scheduled for deployment in Afghanistan, we compared RNT levels between diagnosed groups with alcohol use disorders, anxiety disorders and healthy individuals cross-sectionally. Exploratory analyses were conducted comparing a comorbid disorder-group to healthy individuals and to both single-disorder-groups. Longitudinally, we examined the predictive value of pre-deployment RNT levels for incident psychopathology after deployment (n = 167). RNT was measured using the Perseverative Thinking Questionnaire (PTQ), DSM-IV diagnoses were assessed using the standardized Composite International Diagnostic Interview (CIDI). RESULTS: Cross-sectional comparisons revealed that soldiers with alcohol use disorders and anxiety disorders showed significantly higher degrees of RNT compared to healthy soldiers. RNT levels in those with comorbid disorders were significantly higher compared to healthy soldiers but also compared to both single-disorder-groups. Longitudinal analyses revealed that higher levels of RNT prior to deployment were associated with a higher risk to have any incidental mental disorder after deployment. This however is only attributable to individuals with a PTQ score above a cut-off of 15. CONCLUSIONS: Findings provide evidence for RNT as a transdiagnostic correlate and a vulnerability factor for the development of mental disorders.


Assuntos
Alcoolismo , Militares , Pessimismo , Afeganistão , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , Estudos Transversais , Humanos , Fatores de Risco
6.
Foods ; 9(10)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019534

RESUMO

By-products of fruit and vegetable processing are an inexpensive and sustainable source of dietary fiber, potentially offering valuable functional properties such as water binding and thickening. Due to these favorable properties, they can be utilized to reformulate widely-consumed foods, e.g., bakery products or beverages. In this study, apple pomace was used as a model system to study whether extrusion technology affects food by-product functionality and thus has the potential to broaden the application of by-products in foods. The effect of the process parameters and the extent of thermo-mechanical treatment on the structural and functional properties of apple pomace were analyzed after extrusion trials using various screw speeds, water contents, and barrel temperatures. Compared to the raw material, apple pomace extruded at Tbarrel = 100 °C, n = 700 min-1 and mH2O = 17% showed an increased water solubility up to 33%. The water absorption increased from 5 to 19 Pa·s and the paste viscosity from 5 to 339 Pa·s by extrusion processing. Analyses of dietary fiber contents and fiber polysaccharide structures revealed that thermo-mechanical stress (n = 700 min-1, mH2O = 22%) increased the content of soluble dietary fiber from 12.5 to 16.7 g/100 g dry matter, and that the harshest conditions even enabled the formation of low-molecular-weight dietary fiber. Arabinans (as neutral rhamnogalacturonan I side chains) appeared to be most sensitive to thermo-mechanical stress, whereas xylans (i.e., a group of minor polysaccharides) were an example of a more stable fiber polysaccharide. Also, the degree of methylation of the pectic polysaccharides was strongly reduced from 50% to 15% when thermo-mechanical stress was applied. Imaging and pore size analysis showed that extrusion processing could disrupt the rigid cell wall macromolecular structure.

7.
Food Chem ; 331: 127362, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32590268

RESUMO

The polyphenol compositions of Thymus × citriodorus and Thymus vulgaris extracts as obtained by exhaustive hydroethanolic (HE) extraction and aqueous decoction (AD) were compared. In addition, their compositions and bioactivities were compared to those of Thymus pulegioides and Thymus mastichina, grown under the same edaphoclimatic conditions, and Thymus carnosus. Rosmarinic acid was the most abundant polyphenol followed by luteolin-hexuronide, salvianolic acids I and K. Cluster analysis suggests a similarity of the polyphenol composition of T. citriodorus and T. vulgaris. A significant antioxidant activity was observed and correlated with their polyphenol levels. The same being observed for the higher anti-proliferative activity/cytotoxicity of HE extracts on Caco-2 and HepG2 cells as compared to AD extracts. Significant association between the total phenolic compounds with the anti-proliferative activity, for both cell lines, was observed. These results support the importance of salvianolic acids levels in Thymus extracts and their in vitro anti-proliferative/cytotoxic activities.


Assuntos
Extratos Vegetais/química , Polifenóis/análise , Polifenóis/farmacologia , Thymus (Planta)/química , Alcenos/análise , Antioxidantes/análise , Antioxidantes/farmacologia , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Cinamatos/análise , Análise por Conglomerados , Depsídeos/análise , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Células Hep G2 , Humanos , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Ácido Rosmarínico
8.
Antioxidants (Basel) ; 9(6)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503184

RESUMO

Thymus zygis subsp. zygis is an endemic Portuguese plant belonging to the Thymus zygis species. Although T. zygis is commonly used as a condiment and as a medicinal herb, a detailed description of the polyphenol composition of hydroethanolic (HE) and aqueous decoction (AD) extracts is not available. In this work, we describe for the first time a detailed phenolic composition of Thymus zygis subsp. zygis HE and AD extracts, together with their antioxidant, anti-proliferative and anti-inflammatory activities. Unlike other Thymus species, T. zygis subsp. zygis extracts contain higher amounts of luteolin-(?)-O-hexoside. However, the major phenolic compound is rosmarinic acid, and high amounts of salvianolic acids K and I were also detected. T. zygis subsp. zygis extracts exhibited significant scavenging activity of ABTS+, hydroxyl (•OH), and nitric oxide (NO) radicals. Regarding the anti-proliferative/cytotoxic effect, tested against Caco-2 and HepG2 cells, the AD extract only slightly reduced cell viability at higher concentrations (IC50 > 600 µg/mL, 48 h exposure), denoting very low toxicity, while the HE extract showed a high anti-proliferative effect, especially at 48 h exposure (IC50 of 85.01 ± 15.10 µg/mL and 82.19 ± 2.46 µg/mL, for Caco-2 and HepG2, respectively). At non-cytotoxic concentrations, both extracts reduced the nitric oxide (NO) release by lipopolysaccharide (LPS)-stimulated RAW 264.7 cells (at 50 µg/mL, HE and AD extracts inhibited NO release in ~89% and 48%, respectively). In conclusion, the results highlight the non-toxic effect of aqueous extracts, both resembling the consumption of antioxidants in foodstuff or in functional food. Furthermore, the HE extract of T. zygis subsp. zygis is a source of promising molecules with antioxidant, anti-inflammatory and anticancer activities, highlighting its potential as a source of bioactive ingredients for nutraceutical and pharmaceutical industries.

9.
Glob Change Biol Bioenergy ; 11(1): 191-205, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31007724

RESUMO

Efficient utilization of lignocellulosic Miscanthus biomass for the production of biochemicals, such as ethanol, is challenging due to its recalcitrance, which is influenced by the individual plant cell wall polymers and their interactions. Lignocellulosic biomass composition differs depending on several factors, such as plant age, harvest date, organ type, and genotype. Here, four selected Miscanthus genotypes (Miscanthus sinensis, Miscanthus sacchariflorus, Miscanthus × giganteus, Miscanthus sinensis × Miscanthus sacchariflorus hybrid) were grown and harvested, separated into stems and leaves, and characterized for their non-starch polysaccharide composition and structures, lignin contents and structures, and hydroxycinnamate profiles (monomers and ferulic acid dehydrodimers). Polysaccharides of all genotypes are mainly composed of cellulose and low-substituted arabinoxylans. Ratios of hemicelluloses to cellulose were comparable, with the exception of Miscanthus sinensis that showed a higher hemicellulose/cellulose ratio. Lignin contents of Miscanthus stems were higher than those of Miscanthus leaves. Considering the same organs, the four genotypes did not differ in their Klason lignin contents, but Miscanthus × giganteus showed the highest acetylbromide soluble lignin content. Lignin polymers isolated from stems varied in their S/G ratios and linkage type distributions across genotypes. p-Coumaric acid was the most abundant ester-bound hydroxycinnamte monomer in all samples. Ferulic acid dehydrodimers were analyzed as cell wall cross-links, with 8-5-coupled diferulic acid being the main dimer, followed by 8-O-4-, and 5-5-diferulic acid. Contents of p-coumaric acid, ferulic acid, and ferulic acid dimers varied depending on genotype and organ type. The largest amount of cell wall cross-links was analyzed for Miscanthus sinensis.

10.
Antioxidants (Basel) ; 9(1)2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31906063

RESUMO

Thymus mastichina, also called mastic thyme or Spanish marjoram, is endemic to the Iberian Peninsula, where it is widely used in folk medicine especially for treating digestive and respiratory systems disorders, and as a condiment to season olives. This work describes for the first time the detailed phenolic composition of exhaustive hydroethanolic extracts and aqueous decoctions of Thymus mastichina. Unlike other species of the Thymus genera, Thymus mastichina extracts contain high amounts of salvianolic acid derivatives, with salvianolic acid A isomer being the main derivative. This isomer was identified in extracts from Thymus mastichina for the first time. Also, an undescribed salvianolic acid derivative in Thymus mastichina was identified and its structure was tentatively described. Extracts from Thymus mastichina showed significant scavenging activity of 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical cation, hydroxyl, and nitric oxide radicals. The anti-proliferative effect of both T. mastichina extracts were tested against Caco-2 and HepG2 cells; the hydroethanolic extract showed a high anti-proliferative activity against Caco-2 cells compared to HepG2 cells (at 24 h exposure, the concentration that inhibits 50% of proliferation, IC50, was 71.18 ± 1.05 µg/mL and 264.60 ± 11.78 µg/mL for Caco-2 and HepG2, respectively). Thus, these results make this species a promising candidate for further investigation of its anti-tumoral potential. Therefore, Thymus mastichina can be potentially used as a functional food (used as a decoction or herbal tea) or as a source of bioactive ingredients with antioxidant and anti-proliferative properties.

11.
Behav Res Ther ; 110: 55-63, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30243101

RESUMO

BACKGROUND: The peri-traumatic stress response is a strong predictor of symptom development after trauma exposure. Regarding witnessing trauma, the stress response might depend on the susceptibility to others' emotions (emotional contagion, EC). This study investigated whether EC moderates the immediate stress response using a trauma film paradigm. METHODS: Ninety-five healthy participants were randomly exposed to a trauma or a neutral film. Perceived stressfulness of the film and pre-to post-film changes in self-reported anxiety, heart rate and saliva cortisol levels were assessed. EC towards negative and positive emotions was measured using the emotional contagion scale and its emotion-specific subscales. RESULTS: Overall, the trauma film was perceived as distressing and elicited an increase in self-reported anxiety, heart rate and saliva cortisol levels relative to the neutral film. EC towards negative emotions was positively related to the perceived stressfulness of the film, increased anxiety and increased heart rate. The association with saliva cortisol levels was also in the expected direction, but not statistically significant. These associations were not found for EC towards positive emotions. DISCUSSION: EC towards negative emotions may be an important predictor of trauma exposure outcomes. Further research should clarify its specific contribution in witnessing and undergoing trauma.


Assuntos
Emoções/fisiologia , Autorrelato , Estresse Fisiológico/fisiologia , Ferimentos e Lesões/psicologia , Adolescente , Adulto , Ansiedade/fisiopatologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/metabolismo , Masculino , Estimulação Luminosa , Saliva/metabolismo , Adulto Jovem
12.
Food Funct ; 9(7): 3617-3629, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-29956711

RESUMO

The potential of Thymus pulegioides L. as an alternative and valuable source of functional ingredients has been assessed. For this purpose, the phenolic constituent profiles and the antioxidant, anti-proliferative, neuroprotective, anti-aging and anti-diabetic activities of both T. pulegioides aqueous decoctions (AD) and hydro-ethanolic extracts (HE) were studied and compared for the first time. Rosmarinic acid was the main phenolic compound, accounting for 35.2% or 47.8% of total identified phenols in AD or HE, respectively (58.5 and 151.9 mg g-1 extract). Furthermore, large amounts of luteolin-O-hexuronide (AD: 39.9 ± 2.5 mg g-1, HE: 60.8 ± 7.0 mg g-1), eriodictyol-O-hexuronide (AD: 19.9 ± 2.5 mg g-1, HE: 26.8 ± 7.0 mg g-1) and chrysoeriol hexoside (AD: 23.5 ± 0.7 mg g-1, HE: 16.0 ± 0.7 mg g-1) were found. Both extracts showed significant in vitro antioxidant activity and anti-proliferative activity against Caco-2 cells (IC50 82.25 µg mL-1 and 105.44 µg mL-1, AD and HE, respectively), and reduced hepatotoxicity (HepG2 cells). In general, both T. pulegioides extracts showed poor anti-diabetic activity, moderate anti-aging effects and high neuroprotective activity with both AD and HE extracts, at 0.5 mg mL-1, showing 80% inhibition of the acetylcholinesterase activity and 94% inhibition of the tyrosinase activity. The present study highlights the important potential of this herb as a functional food ingredient.


Assuntos
Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Thymus (Planta)/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Antioxidantes/química , Antioxidantes/isolamento & purificação , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Células Hep G2 , Humanos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
13.
Behav Res Ther ; 102: 60-66, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29353159

RESUMO

BACKGROUND: Fundamental questions regarding the nature and function of attentional bias (AB) to threat in the etiology of posttraumatic stress disorder (PTSD) remain unanswered. We tested the temporal interplay between trauma exposure, dysregulated attentional processing of threatening information pre- and post-trauma, and the development of posttraumatic intrusions. METHODS: Response time to trauma-related threat, trauma-unrelated threat, as well as to trauma-related but typically emotionally-neutral stimuli was assessed using the dot probe task before and one week after watching a violent movie scene that served as a trauma analogue. AB was analyzed as a dynamic process by means of a recently developed approach indexing momentary fluctuations of AB toward and away from emotional stimuli. Posttraumatic intrusions were measured daily over the week following analogue trauma exposure. RESULTS: We found that key features of AB dynamics to trauma-related stimuli at post-, but not pre-, trauma exposure were associated with posttraumatic intrusions. Notably, these post-trauma exposure effects were specific to biased attentional processing of trauma-related but not threatening stimuli unrelated to the traumatic event. In line with a growing body of findings, pre- and post-trauma exposure traditional aggregated mean AB scores were not similarly associated with posttraumatic intrusions. CONCLUSIONS: We conclude that one mechanism through which trauma exposure may contribute to the development of PTSD is through its dysregulation of attentional processing of trauma event-related cues. Future work may focus on delineating the developmental course through which attentional dysregulation post-trauma and posttraumatic intrusions unfold and interact.


Assuntos
Viés de Atenção , Transtornos de Estresse Pós-Traumáticos/psicologia , Ferimentos e Lesões/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Fatores de Risco , Adulto Jovem
14.
J Sci Food Agric ; 98(3): 1016-1023, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28718909

RESUMO

BACKGROUND: Lignified cell walls are important factors for textural and physiological properties of plant-based foods. However, carrot lignins and their modifications during maturation are poorly described. The objective of this study was to describe carrot lignins in detail and to study lignin structural alterations at later stages of maturity. RESULTS: Klason and acetyl bromide soluble lignin contents of insoluble fibers of carrots harvested at different times (26, 29 and 35 weeks after seeding) ranged between 46.38 and 62.68 g kg-1 and between 19.79 and 28.08 g kg-1 , respectively. As determined by both 2D-nuclear magnetic resonance and the derivatization followed by reductive cleavage method, coniferyl alcohol heavily dominated the traditional monolignol composition in carrot lignins, independently of harvest times. By using 2D-nuclear magnetic resonance experiments on isolated lignins, p-hydroxybenzoate was identified as a less common lignin constituent, attached to lignin γ-hydroxyl groups and being increasingly incorporated with maturation. ß-Aryl ethers, phenylcoumaran, resinol and dibenzodioxocin structures were identified as lignin interunit linkages, largely independent of harvest times and with ß-aryl ethers being expectedly dominant. CONCLUSION: Carrots contain guaiacyl-rich lignins that incorporate increasing amounts of p-hydroxybenzoate with maturation. All other lignin characteristics appear to be widely independent of harvest times. © 2017 Society of Chemical Industry.


Assuntos
Daucus carota/química , Daucus carota/crescimento & desenvolvimento , Lignina/metabolismo , Daucus carota/metabolismo , Lignina/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
15.
Food Res Int ; 93: 43-51, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28290279

RESUMO

Storage related changes in the cell wall composition potentially affect the texture of plant-based foods and the physiological effects of cell wall based dietary fiber components. Therefore, a detailed characterization of cell wall polysaccharides and lignins from broccoli stems was performed. Freshly harvested broccoli and broccoli stored at 20°C and 1°C for different periods of time were analyzed. Effects on dietary fiber contents, polysaccharide composition, and on lignin contents/composition were much more pronounced during storage at 20°C than at 1°C. During storage, insoluble dietary fiber contents of broccoli stems increased up to 13%. Storage related polysaccharide modifications include an increase of the portions of cellulose, xylans, and homogalacturonans and a decrease of the neutral pectic side-chains arabinans and galactans. Broccoli stem lignins are generally rich in guaiacyl units. Lignins from freshly harvested broccoli stems contain slightly larger amounts of p-hydroxyphenyl units than syringyl units. Syringyl units are predominantly incorporated into the lignin polymers during storage, resulting in increased acetyl bromide soluble lignin contents. NMR-based analysis of the interunit linkage types of broccoli stem lignins revealed comparably large portions of resinol structures for a guaiacyl rich lignin. Incorporation of syringyl units into the polymers over storage predominantly occurs through ß-O-4-linkages.


Assuntos
Brassica/química , Fibras na Dieta/análise , Armazenamento de Alimentos/métodos , Brassica/ultraestrutura , Configuração de Carboidratos , Parede Celular/química , Lignina/análise , Lignina/química , Espectroscopia de Ressonância Magnética , Caules de Planta/química , Caules de Planta/ultraestrutura , Polissacarídeos/análise , Polissacarídeos/química , Fatores de Tempo
16.
J Agric Food Chem ; 64(45): 8625-8632, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-27744693

RESUMO

Cell wall composition affects the texture of plant-based foods. In addition, the main components of plant cell walls are dietary fiber constituents and are responsible for potential physiological effects that are largely affected by the structural composition of the cell walls. Radish (Raphanus sativus L. var. sativus) is known to develop a woody and firm texture during maturation and ripening, most likely due to changes in the cell wall composition. To describe these changes chemically, radish was cultivated and harvested at different time points, followed by detailed chemical analysis of insoluble fiber polysaccharides and lignin. During maturation, changes in polysaccharide profiles were observed, with a decrease in the portion of neutral pectic side chains and an increase in the xylan portion being predominant. Radish lignin was characterized by unexpectedly high incorporation of p-coumaryl alcohol into the polymer. Maturation dependent increases in lignin contents were accompanied by compositional changes of the lignin polymers with sinapyl alcohol being preferentially incorporated.


Assuntos
Parede Celular/química , Raízes de Plantas/crescimento & desenvolvimento , Raphanus/química , Parede Celular/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Raphanus/crescimento & desenvolvimento , Raphanus/metabolismo
17.
Depress Anxiety ; 33(7): 630-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27175801

RESUMO

BACKGROUND: Attentional bias (AB) to threat is thought to play a key role in the development and maintenance of posttraumatic stress symptomatology (PTS). Empirical evidence though is inconsistent. Some studies report associations between AB towards, threat and PTS; other studies report associations between AB away from threat and PTS; yet other studies fail to find any association. We propose that prospective-longitudinal study of AB as a dynamic process, expressed from moment to moment in time, may help to understand these mixed findings and the role of AB in PTS. METHODS: We tested cross-sectional and prospective-longitudinal associations between AB and PTS among German soldiers from pre- to post-deployment in Afghanistan (n = 144). AB to threat and positive emotion stimuli (angry/happy faces) was measured using the dot-probe task. PTS was assessed by the PTSD Checklist. The number of traumatic experiences was assessed using CIDI-traumatic experience lists for military. RESULTS: We found that AB dynamics (i.e., towards, away, temporal variability) at pre- and post-deployment, with respect to angry and happy faces, predicted higher levels of PTS after deployment as a function of number of intermediate traumatic experiences. Traditional aggregated mean bias scores did not similarly prospectively predict PTS post deployment. CONCLUSIONS: Findings indicate that AB to emotionally arousing stimuli may play an important function in the development and maintenance of PTS. We argue that mixed and null findings appear to be due to failure to model the within-subject temporal variability in AB expression. Theoretical, empirical, and clinical implications of these findings are discussed.


Assuntos
Viés de Atenção/fisiologia , Militares/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Afeganistão , Estudos Transversais , Alemanha , Humanos , Estudos Longitudinais , Masculino , Militares/estatística & dados numéricos , Estudos Prospectivos , Tempo
18.
J Agric Food Chem ; 64(2): 478-86, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26671648

RESUMO

Changes in cell wall composition during storage of plant foods potentially alter the physiological effects of dietary fiber components. To investigate postharvest cell wall modifications of asparagus and their consequences in terms of insoluble dietary fiber structures, asparagus was stored at 20 and 1 °C for different periods of time. Structural analyses demonstrated postharvest changes in the polysaccharide profile, dominated by decreased portions of galactans. Increasing lignin contents correlated with compositional changes (monolignol ratios and linkage types) of the lignin polymer as demonstrated by chemical and two-dimensional nuclear magnetic resonance (2D-NMR) methods. Depending on the storage time and temperature, syringyl units were preferentially incorporated into the lignin polymer. Furthermore, a drastic increase in the level of ester-linked phenolic monomers (i.e., p-coumaric acid and ferulic acid) and polymer cross-links (di- and triferulic acids) was detected. The attachment of p-coumaric acid to lignin was demonstrated by 2D-NMR experiments. Potential consequences of postharvest modifications on physiological effects of asparagus dietary fiber are discussed.


Assuntos
Asparagus/química , Parede Celular/química , Fibras na Dieta/análise , Polissacarídeos/química , Verduras/química , Asparagus/metabolismo , Parede Celular/metabolismo , Fibras na Dieta/metabolismo , Armazenamento de Alimentos , Estrutura Molecular , Polissacarídeos/metabolismo , Verduras/metabolismo
19.
J Behav Ther Exp Psychiatry ; 48: 133-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25863483

RESUMO

BACKGROUND AND OBJECTIVES: Attentional processes have been suggested to play a crucial role in resilience defined as positive adaptation facing adversity. However, research is lacking on associations between attentional biases to positive and threat-related stimuli, attentional control and trait resilience. METHODS: Data stem from the follow-up assessment of a longitudinal study investigating mental health and related factors among German soldiers. Trait resilience was assessed with the Connor-Davidson Resilience Scale and attentional control with the Attentional Control Scale. A subset of n = 198 soldiers also completed a dot probe task with happy, neutral and threatening faces. RESULTS: Attentional control was positively related to trait resilience. Results revealed no associations between both attentional biases and trait resilience. However, there was a negative association between attentional bias to threat and trait resilience when attentional control was low and a positive association between attentional bias to threat and trait resilience when attentional control was high. No such associations were found for attentional bias to positive stimuli. LIMITATIONS: Generalizability to other populations may be limited since we exclusively focused on male soldiers. Also, the cross-sectional design does not allow for causal conclusions. CONCLUSIONS: Findings suggest that attentional processing may promote trait resilience. Future research on preventive interventions should consider these findings.


Assuntos
Atenção/fisiologia , Emoções/fisiologia , Função Executiva/fisiologia , Militares/psicologia , Resiliência Psicológica , Adulto , Seguimentos , Humanos , Masculino , Adulto Jovem
20.
J Agric Food Chem ; 63(10): 2668-73, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25727138

RESUMO

The derivatization followed by reductive cleavage (DFRC) method is a well-established tool to characterize the lignin composition of plant materials. However, the application of the original procedure, especially the chromatographic determination of the DFRC monomers, is problematic for low-lignin foods. To overcome these problems a modified sample cleanup and a stable-isotope dilution approach were developed and validated. To quantitate the diacetylated DFRC monomers, their corresponding hexadeuterated analogs were synthesized and used as internal standards. By using the selected-ion monitoring mode, matrix-associated interferences can be minimized resulting in higher selectivity and sensitivity. The modified method was applied to four low-lignin samples. Lignin from carrot fibers was classified as guaiacyl-rich whereas the lignins from radish, pear, and asparagus fibers where classified as balanced lignins (guaiacyl/syringyl ratio=1-2).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Técnicas de Diluição do Indicador , Lignina/química , Verduras/química , Estrutura Molecular , Oxirredução
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