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Purinergic Signalling - After more than two decades of preclinical and clinical studies, on August 27, 2019, the US Food and Drug Administration (FDA) approved the adenosine A2A receptor antagonist...  相似文献   
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Fin clips have been proposed as a non-lethal and non-invasive alternative to dorsal muscle samples in stable isotope analysis. However, potential differences in elemental composition and turnover rates can bias inferences when different tissues are combined. Here, we tested the average difference and correlation of the isotopic signature of δ13C and δ15N between muscle and fin samples in two arge-bodied fishes: Longnose Gar (Lepisosteus osseus) and Smallmouth Buffalo (Ictiobus bubalus). We found that δ15N signatures of muscle and fin tissues were strongly and positively correlated for both species, although the muscle tissue for Smallmouth Buffalo was slightly more enriched in δ15N. δ13C signatures of both tissues were significatively different and not strongly correlated for Longnose Gar, but similar and strongly correlated for Smallmouth Buffalo. Our results suggest that fin and muscle tissue can be combined for analyses of δ15N, but correction for higher enrichment of muscle tissue may be necessary for Smallmouth Buffalo. Conversely, combining fin and muscle tissue for analysis of δ13C requires more caution due to their weaker correlation and dependence of species identity.  相似文献   
35.
Salvador  Rodrigo B.  Cunha  Carlo M. 《Oecologia》2020,192(3):641-646
Oecologia - Natural history collections are now being championed as key to broad ecological studies, especially those involving human impacts in the Anthropocene. However, collections are going...  相似文献   
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Whey proteins (WP) gelation process with addition of Arabic gum (AG) was studied. Two different driving processes were employed to induce gelation: (1) heating of 12% whey protein isolate (WPI) solutions (w/w) or (2) acidification of previous thermal denatured WPI solutions (5% w/w) with glucono-δ-lactone (GDL). Protein concentrations were different because they were minimal to form gel in these two processes, but denaturation conditions were the same (90 °C/30 min). Water-holding capacity and mechanical properties of the gels were evaluated. The BST equation was used to evaluate the nonlinear part of the stress–strain data. Cold-set gels were weaker than heat-set gels at the pH range near the isoelectric point (pI) of the main whey proteins, but heated gels were more deformable (did not exhibit rupture point) and showed greater elasticity modulus. However, gels formed by heating far from the pI (pH 6.7 or 3.5) showed more fragile structure, indicating that, in these mixed gels, there are prevailing biopolymers interactions. Cold-set and heat-set gels at pH near or below the WP pI showed strain-weakening behavior, but heated gels at neutral pH showed strong strain-hardening behavior. Such results suggest that differences in stress–strain curve at the nonlinear part of the data could be correlated to structure particularities obtained from different gelation processes.  相似文献   
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Background  

Staphylococcus aureus methicillin-resistant (MRSA) has been frequently isolated from endotracheal and lung puncture aspirates in malnourished children with pneumonia. In this work we evaluated the susceptibility of undernourished BALB/c mice and its ability to mount a protective immunity against MRSA with emphasis on the lung involvement.  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   
39.
The breeding system of Eichhornia azurea (Pontederiaceae) has been described as being both self- and heteromorphic incompatible based on crossing experiments performed on plants grown in an experimental garden. We studied the breeding system of tristylous E. azurea population under natural conditions in the Pantanal wetlands, Brazil. Controlled pollinations were conducted using 35 individuals of each floral morph. Legitimate pollinations produced more fruits than self- and illegitimate pollinations, except for the mid-styled morph which was highly self- and heteromorphic compatible. The number of seeds per fruit was higher under legitimate pollinations than in the other treatments, but self- and illegitimate pollinations produced more fruits and seeds in the Pantanal than for individuals of E. azurea in other populations. The higher fruit and seed production resulting from legitimate pollinations corroborate previous studies, but self-compatibility of mid-styled plants was not previously reported. Overall results indicate a partially self- and heteromorphic compatible system for this species in the Pantanal.  相似文献   
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This paper describes the synthesis, antiplatelet and theoretical evaluations of 10 N-substituted-phenylamino-5-methyl-1H-1,2,3-triazole-4-carbohydrazides (2aj). These compounds were synthesized, characterized and screened for their in vitro antiplatelet profile against human platelet aggregation using arachidonic acid, adrenaline and ADP as agonists. Among NAH derivatives 2aj, the compounds 2a, 2c, 2e, 2g and 2h were the most promising molecules with significant antiplatelet activity.  相似文献   
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