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21.
This study compared the antinociceptive effect produced by cathodic iontophoresis of sodium diclofenac close to an arthritic knee-joint in rats with that of systemic application. Arthritic nocifensive incapacitation was induced by LPS (1 microg) injection into a knee-joint previously (72 h) primed with carrageenan (300 microg). Diclofenac (0.1, 0.25 and 0.5 mg/kg) given intraperitoneally 1 h after LPS injection caused dose-dependent inhibition of incapacitation. Diclofenac iontophoresis was performed by varying either the current density (0.1, 0.2, and 0.3 mA/cm2) or the duration of application (4, 10, 20 and 30 min) of a polyvinylpirrolydone-hydroxymethylcellulose gel containing 1% sodium diclofenac. A clear, current density-dependent effect was observed for 0.1, 0.2 and 0.3 mA/cm2 (10 min period), which was similar to the effect observed for the intraperitoneal application of 0.1, 0.25 and 0.5 mg/kg doses. Combining different application periods with different current densities, in a manner that resulted in the same total current (1.6 mA*min) application, did not produce similar therapeutic effects, but the antinociceptive effect was directly proportional to the current density. The ipsilateral iontophoresis (0.25 mA/cm2 x 10 min or 0.5 mA/cm2 x 4 min) of diclofenac produced an effect significantly greater than the same contralateral application (p<0.05). In conclusion, our results suggest that the therapeutic effect depends on the current density but not on the application time, and also that the iontophoretic, direct application to the inflamed knee-joint enhances the therapeutic effect probably as a result of the direct delivery of the drug.  相似文献   
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Journal of Plant Growth Regulation - The rising demand for agricultural commodities in developing countries has put increasing pressure on land resources for higher yields, with associated growth...  相似文献   
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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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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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Inorganic polyphosphate (PolyP) is a biological polymer that plays important roles in the cell physiology of both prokaryotic and eukaryotic organisms. Among the available methods for PolyP localization and quantification, a 4’,6-diamidino-2-phenylindole(DAPI)-based assay has been used for visualization of PolyP-rich organelles. Due to differences in DAPI permeability to different compartments and/or PolyP retention after fixation, a general protocol for DAPI-PolyP staining has not yet been established. Here, we tested different protocols for DAPI-PolyP detection in a range of samples with different levels of DAPI permeability, including subcellular fractions, free-living cells and cryosections of fixed tissues. Subcellular fractions of PolyP-rich organelles yielded DAPI-PolyP fluorescence, although those with a complex external layer usually required longer incubation times, previous aldehyde fixation and/or detergent permeabilization. DAPI-PolyP was also detected in cryosections of OCT-embedded tissues analyzed by multiphoton microscopy. In addition, a semi-quantitative fluorimetric analysis of DAPI-stained fractions showed PolyP mobilization in a similar fashion to what has been demonstrated with the use of enzyme-based quantitative protocols. Taken together, our results support the use of DAPI for both PolyP visualization and quantification, although specific steps are suggested as a general guideline for DAPI-PolyP staining in biological samples with different degrees of DAPI and PolyP permeability.Key words: DAPI, polyphosphate, fluorescence, fluorimetry  相似文献   
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