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Molecular Biology Reports - There is a lack of evidence on the effects of high-intensity interval training (HIIT) microcycle duration on the antioxidant capacity and hippocampal inflammatory...  相似文献   
993.
Molecular Biology Reports - Prodiginines are bacterial red polypyrrole pigments and multifaceted secondary metabolites. These agents have anti-proliferative, immunosuppressive, antimicrobial, and...  相似文献   
994.
An imbalance between caloric intake and energy expenditure leads to obesity. Obesity is an important risk factor for the development of several metabolic diseases including insulin resistance, metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. So, controlling obesity could be effective in the improvement of obesity-related diseases. Various factors are involved in obesity, such as AMP-activated protein kinases (AMPK), silent information regulators, inflammatory mediators, oxidative stress parameters, gastrointestinal hormones, adipokines, angiopoietin-like proteins, and microRNAs. These factors play an important role in obesity by controlling fat metabolism, energy homeostasis, food intake, and insulin sensitivity. AMPK is a heterotrimeric serine/threonine protein kinase known as a fuel-sensing enzyme. The central role of AMPK in obesity makes it an attractive molecule to target obesity and related metabolic diseases. In this review, the critical role of AMPK in obesity and the interplay between AMPK and obesity-associated factors were elaborated.  相似文献   
995.
In the field of brain research, attention as one of the main issues in cognitive neuroscience is an important mechanism to be studied. The complicated structure of the brain cannot process all the information it receives at any moment. Attention, in fact, is considered as a possible useful mechanism in which brain concentrates on the processing of important information which is required at any certain moment. The main goal of this study is decoding the location of visual attention from local field potential signals recorded from medial temporal (MT) area of a macaque monkey. To this end, feature extraction and feature selection are applied in both the time and the frequency domains. After applying feature extraction methods such as the short time Fourier transform, continuous wavelet transform (CWT), and wavelet energy (scalogram), feature selection methods are evaluated. Feature selection methods used here are T-test, Entropy, receiver operating characteristic, and Bhattacharyya. Subsequently, different classifiers are utilized in order to decode the location of visual attention. At last, the performances of the employed classifiers are compared. The results show that the maximum information about the visual attention in area MT exists in the low frequency features. Interestingly, low frequency features over all the time-axis and all of the frequency features at the initial time interval in the spectrogram domain contain the most valuable information related to the decoding of spatial attention. In the CWT and scalogram domains, this information exists in the low frequency features at the initial time interval. Furthermore, high performances are obtained for these features in both the time and the frequency domains. Among different employed classifiers, the best achieved performance which is about 84.5 % belongs to the K-nearest neighbor classifier combined with the T-test method for feature selection in the time domain. Additionally, the best achieved result (82.9 %) is related to the spectrogram with the least number of selected features as large as 200 features using the T-test method and SVM classifier in the time−frequency domain.  相似文献   
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Milk thistle (Silybum marianum) is a medicinal plant; however, lack of consistency in past dormancy studies has hindered propagation of this species from seeds. We tested the germination responses of freshly harvested and after-ripened (stored for 2 and 7 months; 25°C at 50% relative humidity) seeds from three populations (P1, P2 and P3) in Iran at varying constant or alternating temperatures, with or without GA3 and in light and continuous darkness. No germination occurred in freshly harvested seeds incubated at any condition without GA3 application, indicating that all the seeds were dormant. Seeds from P1 and P2, which developed under relatively dry, warm conditions, germinated over a wider range of temperatures after 2 months of dry storage, indicating type 6 of non-deep physiological dormancy (PD). Seeds from P3, which developed under relatively wet, cool conditions, incubated at constant temperatures (especially on GA3), exhibited an increase in maximum temperature for germination, indicating type 1 of non-deep PD. Light improved germination of after-ripened seeds, and GA3 application substituted for the light requirement for germination. This is the first report that environmental conditions during seed development may be correlated with differences in the type of non-deep PD. We conclude that milk thistle seeds are positively photoblastic and photodormant and the germination responses of after-ripened seeds from different populations are different under darkness. Therefore, the impacts of genetic differences and maternal effects on the induction of dormancy during seed development should be considered in attempts to domesticate this medicinal plant.  相似文献   
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Food Biophysics - This study aimed to extract betaine from sugar beet molasses using the cloud point method and encapsulate it in fast-dissolving fibers of Poly(vinyl alcohol) (PVA)/Plantago ovata...  相似文献   
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Autophagy plays critical roles in the maintenance of endothelial cells in response to cellular stress caused by blood flow. There is growing evidence that both cell adhesion and cell detachment can modulate autophagy, but the mechanisms responsible for this regulation remain unclear. Immunoglobulin and proline-rich receptor-1 (IGPR-1) is a cell adhesion molecule that regulates angiogenesis and endothelial barrier function. In this study, using various biochemical and cellular assays, we demonstrate that IGPR-1 is activated by autophagy-inducing stimuli, such as amino acid starvation, nutrient deprivation, rapamycin, and lipopolysaccharide. Manipulating the IκB kinase β activity coupled with in vivo and in vitro kinase assays demonstrated that IκB kinase β is a key serine/threonine kinase activated by autophagy stimuli and that it catalyzes phosphorylation of IGPR-1 at Ser220. The subsequent activation of IGPR-1, in turn, stimulates phosphorylation of AMP-activated protein kinase, which leads to phosphorylation of the major pro-autophagy proteins ULK1 and Beclin-1 (BECN1), increased LC3-II levels, and accumulation of LC3 punctum. Thus, our data demonstrate that IGPR-1 is activated by autophagy-inducing stimuli and in response regulates autophagy, connecting cell adhesion to autophagy. These findings may have important significance for autophagy-driven pathologies such cardiovascular diseases and cancer and suggest that IGPR-1 may serve as a promising therapeutic target.  相似文献   
1000.
The complement anaphylatoxin C5a is a proinflammatory component of host defense that functions through two identified receptors, C5a receptor (C5aR) and C5L2. C5aR is a classical G protein-coupled receptor, whereas C5L2 is structurally homologous but deficient in G protein coupling. In human neutrophils, we show C5L2 is predominantly intracellular, whereas C5aR is expressed on the plasma membrane. Confocal analysis shows internalized C5aR following ligand binding is co-localized with both C5L2 and β-arrestin. Antibody blockade of C5L2 results in a dramatic increase in C5a-mediated chemotaxis and ERK1/2 phosphorylation but does not alter C5a-mediated calcium mobilization, supporting its role in modulation of the β-arrestin pathway. Association of C5L2 with β-arrestin is confirmed by cellular co-immunoprecipitation assays. C5L2 blockade also has no effect on ligand uptake or C5aR endocytosis in human polymorphonuclear leukocytes, distinguishing its role from that of a rapid recycling or scavenging receptor in this cell type. This is thus the first example of a naturally occurring seven-transmembrane segment receptor that is both obligately uncoupled from G proteins and a negative modulator of signal transduction through the β-arrestin pathway. Physiologically, these properties provide the possibility for additional fine-tuning of host defense.  相似文献   
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