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International Journal of Biometeorology - Lying behavior is an important indicator of the cows’ welfare and health. In this study, we evaluate the effect of the physical environment on dairy...  相似文献   
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Epigenetic histone trimethylation on lysine 9 (H3K9me3) represents a major molecular signal for genome stability and gene silencing conserved from worms to man. However, the functional role of the H3K9 trimethylases SUV39H1/2 in mammalian tissue homeostasis remains largely unknown. Here, we use a spontaneous dog model with monogenic inheritance of a recessive SUV39H2 loss-of-function variant and impaired differentiation in the epidermis, a self-renewing tissue fueled by stem and progenitor cell proliferation and differentiation. Our results demonstrate that SUV39H2 maintains the stem and progenitor cell pool by restricting fate conversion through H3K9me3 repressive marks on gene promoters encoding components of the Wnt/p63/adhesion axis. When SUV39H2 function is lost, repression is relieved, and enhanced Wnt activity causes progenitor cells to prematurely exit the cell cycle, a process mimicked by pharmacological Wnt activation in primary canine, human, and mouse keratinocytes. As a consequence, the stem cell growth potential of cultured SUV39H2-deficient canine keratinocytes is exhausted while epidermal differentiation and genome stability are compromised. Collectively, our data identify SUV39H2 and potentially also SUV39H1 as major gatekeepers in the delicate balance of progenitor fate conversion through H3K9me3 rate-limiting road blocks in basal layer keratinocytes.  相似文献   
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This study aimed to evaluate the impact of aerobic training (AT) on autonomic, cardiometabolic, ubiquitin‐proteasome activity, and inflammatory changes evoked by myocardial infarction (MI) in ovariectomized rats. Female Wistar rats were ovariectomized and divided into four groups: sedentary + sham (SS), sedentary + MI (SI), AT + sham surgery (TS), AT + MI (TI). AT was performed on a treadmill for 8 weeks before MI. Infarcted rats previously subjected to AT presented improved physical capacity, increased interleukin‐10, and decreased pro‐inflammatory cytokines. Metabolomic analysis identified and quantified 62 metabolites, 9 were considered significant by the Vip Score. SS, SI, and TS groups presented distinct metabolic profiles; however, TI could not be distinguished from the SS group. MI dramatically increased levels of dimethylamine, and AT prevented this response. Our findings suggest that AT may be useful in preventing the negative changes in functional, inflammatory, and metabolic parameters related to MI in ovariectomized rats.  相似文献   
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Cellular and Molecular Neurobiology - Activation of μ, δ, and κ opioid receptors by endogenous opioid peptides leads to the regulation of many emotional and physiological responses....  相似文献   
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Antimicrobial peptides (AMPs) are molecules present in several life forms, possess broad-spectrum of inhibitory activity against pathogenic microorganisms, and are a promising alternative to combat the multidrug resistant pathogens. The aim of this work was to identify and characterize AMPs from Capsicum chinense fruits and to evaluate their inhibitory activities against yeasts of the genus Candida and α-amylases. Initially, after protein extraction from fruits, the extract was submitted to anion exchange chromatography resulting two fractions. Fraction D1 was further fractionated by molecular exclusion chromatography, and three fractions were obtained. These fractions showed low molecular mass peptides, and in fraction F3, only two protein bands of approximately 6.5 kDa were observed. Through mass spectrometry, we identified that the lowest molecular mass protein band of fraction F3 showed similarity with AMPs from plant defensin family. We named this peptide CcDef3 (Capsicum chinense defensin 3). The antifungal activity of these fractions was analyzed against yeasts of the genus Candida. At 200 μg/mL, fraction F1 inhibited the growth of C. tropicalis by 26%, fraction F2 inhibited 35% of the growth of C. buinensis, and fraction F3 inhibited all tested yeasts, exhibiting greater inhibition activity on the growth of the yeast C. albicans (86%) followed by C. buinensis (69%) and C. tropicalis (21%). Fractions F1 and F2 promoted membrane permeabilization of all tested yeasts and increased the endogenous induction of reactive oxygen species (ROS) in C. buinensis and C. tropicalis, respectively. We also observed that fraction F3 at a concentration of 50 µg/mL inhibited the α-amylase activities of Tenebrio molitor larvae by 96% and human salivary by 100%. Thus, our results show that fraction F3, which contains CcDef3, is a very promising protein fraction because it has antifungal potential and is able to inhibit the activity of different α-amylase enzymes.

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In this work, two synthetic aurones revealed moderate schistosomicidal potential in in vitro and in vivo assays. Aurones ( 1 ) and ( 2 ) promoted changes in tegument integrity and motor activity, leading to death of adult Schistosoma mansoni worms in in vitro assays. When administered orally (two doses of 50 mg/kg) in experimentally infected animals, synthetic aurones ( 1 ) and ( 2 ) promoted reductions of 56.20 % and 57.61 % of the parasite load and stimulated the displacement towards the liver of the remaining adult worms. The oogram analysis revealed that the treatment with both aurones interferes with the egg development kinetics in the intestinal tissue. Seeking an action target for compounds ( 1 ) and ( 2 ), the connection with NTPDases enzymes, recognized as important therapeutic targets for S. mansoni, was evaluated. Molecular docking studies have shown promising results. The dataset reveals the anthelmintic character of these compounds, which can be used in the development of new therapies for schistosomiasis.  相似文献   
59.
Hundreds of millions of people worldwide are affected by Chagas’ disease caused by Trypanosoma cruzi. Since the current treatment lack efficacy, specificity, and suffers from several side-effects, novel therapeutics are mandatory. Natural products from endophytic fungi have been useful sources of lead compounds. In this study, three lactones isolated from an endophytic strain culture were in silico evaluated for rational guidance of their bioassay screening. All lactones displayed in vitro activity against T. cruzi epimastigote and trypomastigote forms. Notably, the IC50 values of (+)-phomolactone were lower than benznidazole (0.86 vs. 30.78 μM against epimastigotes and 0.41 vs. 4.88 μM against trypomastigotes). Target-based studies suggested that lactones displayed their trypanocidal activities due to T. cruzi glyceraldehyde-3-phosphate dehydrogenase (TcGAPDH) inhibition, and the binding free energy for all three TcGAPDH-lactone complexes suggested that (+)-phomolactone has a lower score value (−3.38), corroborating with IC50 assays. These results highlight the potential of these lactones for further anti-T. cruzi drug development.  相似文献   
60.
Gomes  Milena  Cazetta  Eliana  Bovendorp  Ricardo  Faria  Deborah 《Plant Ecology》2021,222(10):1143-1155

The Atlantic Forest is one of the most threatened tropical forests in the world, being drastically reduced, fragmented, and disturbed. The drastic process of anthropic occupation and exploitation of this biome has, in many cases, led to the introduction of exotic species, such as the jackfruits (Artocarpus heterophyllus). However, studies on the influence of jackfruits on the native biota are still scarce. Here we investigated the influence of fruit trees on the seed rain and early recruitment of seedlings in native remnants, comparing these patterns with those observed for a native species tapirira (Tapirira guianensis), which similarly to jackfruits, produces many fruits throughout the year, attracting a variety of frugivore species. Seed rain and seedlings observed under the jackfruits were both more abundant and equally rich to the assemblages reported under the native tapirira trees. In both species, co-specifics comprise a large part of the number of seeds (>?70%) and seedlings (>?45%) individuals and, although they attract similar seed assemblages, seedling composition diverge, particularly when co-specifics are excluded. We reported that jackfruits can attract a diverse seed and seedling assemblages, and we find no evidence that the presence of jackfruits negatively affects the arrival and initial recruitment of native plant species in the study area. These results should be analyzed with caution but considered when evaluating costs and benefits of management options to control exotic species.

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