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981.
Cecilia L. Salcedo Beatriz A. López de Mishima Mónica A. Nazareno 《Food research international (Ottawa, Ont.)》2010,43(4):1187-1197
Walnuts and almonds were selected as complex model systems in order to study possible interactions among oxidisable substances, pro-oxidant species and antioxidants. Lipoxygenase activities in a direct-micelle system were determined for these nuts according their globulin contents in their soluble protein fraction. Walnut lipoxygenase activity was 1.5 times higher than that of almonds. Among antioxidant compounds, hydrophilic contents were analysed in these nuts, hence, extractable, hydrolysable and condensed phenolic compound fractions were determined as well as lipophilic phenolic concentration corresponding to tocopherol fraction. Extracts of brown skins and whole walnuts have significantly higher phenolic contents than those of almonds. Radical scavenging activities of phenolic extracts were measured. Besides, the experiments demonstrated the ability of all nut extracts to inhibit the coupled oxidation of linoleic acid with β-carotene induced by lipoxygenase. The antioxidant substances were mainly found in nut brown skins. Walnut extracts showed higher antioxidant activity than those of almonds. Lipoxygenase pro-oxidant activity was also measured in AOT reverse micelles in conditions that model these nuts. 相似文献
982.
Erasmo Herman-Lara Cecilia E. Martínez-Sánchez Hermelinda Pacheco-Angulo Roselis Carmona-García Héctor Ruiz-Espinosa Irving I. Ruiz-López 《Food and Bioproducts Processing》2013,91(3):216-224
Equilibrium and dynamic mass transfer properties of water and solute were investigated during osmotic dehydration (OD) of radish slices in sodium chloride (NaCl) solutions. OD experiments were performed in 0.05, 0.15 and 0.25 g/g solutions at different temperatures (25, 40, 55 and 70 °C) using a brine-to-vegetable mass ratio of 15:1. An analytical solution for unsteady-state mass transfer based on Fick's second law of diffusion was used to mathematically describe water loss and solute gain curves and for the simultaneous estimation of diffusion coefficients and final dehydration–impregnation levels in product. Under such experimental conditions, effective water diffusivity was in the range of 1.85–2.74 × 10?9 m2/s, whereas solute diffusivity values were between 0.74 × 10?9 and 2.88 × 10?9 m2/s. Corresponding dehydration and impregnation levels of radish at equilibrium were estimated between 0.25 and 0.81 g water/g fresh product and 0.01–0.11 g solute/g fresh product, respectively. As demonstrated, current results may be applied to determine the set of conditions (process time, brine concentration and process temperature) yielding an osmodehydrated radish product within given specifications. 相似文献
983.
Gastón Ares Rosires Deliza Cecilia Barreiro Ana Giménez Adriana Gámbaro 《Food quality and preference》2010,21(4):417-426
Eight chocolate milk desserts with different formulation were evaluated by two groups of consumers. Fifty consumers evaluated the samples and indicated their overall liking and answered a CATA question. Meanwhile, 40 consumers elicited up to four words to describe the desserts and completed a projective mapping task. Projective mapping and the check-all-that-apply question provided very similar sensory profiles for the evaluated milk desserts. Differences in the sensory characteristics of the samples were explained by differences in their formulations, which suggest the validity of the sensory profiles given by consumers. Projective mapping and the CATA question consisted on valuable tools to understand their perception of the sensory and hedonic characteristics of the desserts. These methodologies could consist on useful and interesting complimentary techniques to trained assessors’ data, being CATA question easier to understand and less time consuming for consumers. 相似文献
984.
985.
Yu. S. Zaslavsky A. A. Berlin R. N. Zaslavsky M. I. Cherkashin K. E. Beloserova V. A. Rusakova 《Wear》1972,20(3):287-297
A new type of additive for oils and fuels has been developed. These additives, ashless organic compounds forming friction polymers, provide simultaneous antiwear, extreme pressure and antifriction action. The results of four-ball testing of antiwear, extreme pressure and antifriction action of the additives are presented. Their ability to form friction polymers on rubbing metal surfaces was confirmed by radiotracer investigations. 相似文献
986.
试图用Muller模型解释全方位记忆行为,并提出:全方位记忆效应,实质上是试样内、外层两种不同取向的应力诱发马氏体(及R相)的可逆相变过程。 相似文献
987.
Andrea Olmos-Ortiz Mayra Hernndez-Prez Pilar Flores-Espinosa Gabriela Sedano Addy Cecilia Helguera-Repetto
scar Villavicencio-Carrisoza María Yolotzin Valdespino-Vazquez Arturo Flores-Pliego Claudine Irles Bruno Rivas-Santiago Elsa Romelia Moreno-Verduzco Lorenza Díaz Vernica Zaga-Clavellina 《International journal of molecular sciences》2022,23(6)
An infectious process into the uterine cavity represents a major endangered condition that compromises the immune privilege of the maternal–fetal unit and increases the risk for preterm birth (PTB) and premature rupture of membranes (PROM). Fetal membranes are active secretors of antimicrobial peptides (AMP), which limit bacterial growth, such as Escherichia coli. Nevertheless, the antibacterial responses displayed by chorioamniotic membranes against a choriodecidual E. coli infection have been briefly studied. The objective of this research was to characterize the profile of synthesis, activity, and spatial distribution of a broad panel of AMPs produced by fetal membranes in response to E. coli choriodecidual infection. Term human chorioamniotic membranes were mounted in a two independent compartment model in which the choriodecidual region was infected with live E. coli (1 × 105 CFU/mL). Amnion and choriodecidual AMP tissue levels and TNF-α and IL-1β secretion were measured by the enzyme-linked immunosorbent assay. The passage of bacterium through fetal membranes and their effect on structural continuity was followed for 24 h. Our results showed that E. coli infection caused a progressive mechanical disruption of the chorioamniotic membranes and an activated inflammatory environment. After the challenge, the amnion quickly (2–4 h) induced production of human beta defensins (HBD)-1, HBD-2, and LL-37. Afterwards (8–24 h), the amnion significantly produced HBD-1, HBD-2, HNP-1-3, S100A7, sPLA2, and elafin, whereas the choriodecidua induced LL-37 synthesis. Therefore, we noticed a temporal- and tissue-specific pattern regulation of the synthesis of AMPs by infected fetal membranes. However, fetal membranes were not able to contain the collagen degradation or the bacterial growth and migration despite the battery of produced AMPs, which deeply increases the risk for PTB and PROM. The mixture of recombinant HBDs at low concentrations resulted in increased bactericidal activity compared to each HBD alone in vitro, encouraging further research to study AMP combinations that may offer synergy to control drug-resistant infections in the perinatal period. 相似文献
988.
Rossella Gratton Cecilia Del Vecchio Luisa Zupin Sergio Crovella 《International journal of molecular sciences》2022,23(6)
The skin exerts several fundamental functions that are the first physical, chemical and immune barriers to the human body. Keratinocytes, the main cell type of the epidermis, provide mechanical defense, support skin integrity and actively endorse cutaneous immune responses. Not surprisingly, considering these crucial activities, alterations in keratinocyte functions are associated with different inflammatory skin diseases. Recent findings indicate that the skin should not only be regarded as a target for hormones but that it should also be considered as an endocrine peripheral organ that is directly involved in the synthesis and metabolism of these chemical messengers. Sex hormones have multiple effects on the skin, attributed to the binding with intracellular receptors expressed by different skin cell populations, including keratinocytes, that activate downstream signaling routes that modulate specific cellular functions and activities. This review is aimed at reorganizing the current knowledge on the role exerted by sex hormones on keratinocyte function in five different inflammatory skin diseases: Hidradenitis suppurativa; Acne vulgaris; Atopic dermatitis; progesterone hypersensitivity; psoriasis. The results of our work aim to provide a deeper insight into common cellular mechanisms and molecular effectors that might constitute putative targets to address for the development of specific therapeutic interventions. 相似文献
989.
Dilip Kumar Malipatlolla Sravani Devarakonda Piyush Patel Fei Sjberg Ana Rascn Rita Grandr Viktor Skokic Marie Kalm Jolie Danial Eva Mehdin Malin Warholm Henrietta Norling Andrea Stringer Malin E. V. Johansson Margareta Nyman Gunnar Steineck Cecilia Bull 《International journal of molecular sciences》2022,23(1)
Dietary fiber is considered a strong intestinal protector, but we do not know whether dietary fiber protects against the long-lasting mucosal damage caused by ionizing radiation. To evaluate whether a fiber-rich diet can ameliorate the long-lasting pathophysiological hallmarks of the irradiated mucosa, C57BL/6J mice on a fiber-rich bioprocessed oat bran diet or a fiber-free diet received 32 Gray in four fractions to the distal colorectum using a linear accelerator and continued on the diets for one, six or 18 weeks. We quantified degenerating crypts, crypt fission, cell proliferation, crypt survival, macrophage density and bacterial infiltration. Crypt loss through crypt degeneration only occurred in the irradiated mice. Initially, it was most frequent in the fiber-deprived group but declined to levels similar to the fiber-consuming group by 18 weeks. The fiber-consuming group had a fast response to irradiation, with crypt fission for growth or healing peaking already at one week post-irradiation, while crypt fission in the fiber-deprived group peaked at six weeks. A fiber-rich diet allowed for a more intense crypt cell proliferation, but the recovery of crypts was eventually lost by 18 weeks. Bacterial infiltration was a late phenomenon, evident in the fiber-deprived animals and intensified manyfold after irradiation. Bacterial infiltration also coincided with a specific pro-inflammatory serum cytokine profile. In contrast, mice on a fiber-rich diet were completely protected from irradiation-induced bacterial infiltration and exhibited a similar serum cytokine profile as sham-irradiated mice on a fiber-rich diet. Our findings provide ample evidence that dietary fiber consumption modifies the onset, timing and intensity of radiation-induced pathophysiological processes in the intestinal mucosa. However, we need more knowledge, not least from clinical studies, before this finding can be introduced to a new and refined clinical practice. 相似文献
990.
This research sought to formulate a theoretically based conceptualization of coping flexibility and to adopt a multimethod approach in assessing this construct. A self-report daily measure and an experiment were designed geared to theoretical and empirical grounds. The new daily measure was used in Study 1 to examine coping flexibility in a life transition. Findings showed individual differences in patterns of coping flexibility across different real-life stressful events. In Study 2, coping flexibility was examined in both real-life and laboratory settings. Results replicated those of Study 1 and further revealed consistency between the self-report and the experiment data. Study 3 extended previous studies by adopting a longitudinal design over a 3-month time span. Participants' flexibility in coping with laboratory tasks was found to predict how flexible they would be in handling real-life stressful events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献