CBA macrophages effectively control Leishmania major infection, yet are permissive to Leishmania amazonensis. Employing a transcriptomic approach, we previously showed the up-regulation of the genes ...involved in the classical pathway of macrophage activation in resistant mice. However, microarray analyses do not evaluate changes in gene expression that occur after translation. To circumvent this analytical limitation, we employed a proteomics approach to increase our understanding of the modulations that occur during infection and identify novel targets for the control of Leishmania infection. To identify proteins whose expression changes in CBA macrophages infected with L. major or L. amazonensis, protein extracts were obtained and digested and the peptides were characterized using multi-dimensional liquid chromatography coupled with tandem mass spectrometry analyses. A total of 162 proteins were selected as potentially modulated. Using biological network analyses, these proteins were classified as primarily involved in cellular metabolism and grouped into cellular development biological networks. This study is the first to use a proteomics approach to describe the protein modulations involved in cellular metabolism during the initial events of Leishmania–macrophage interaction. Based on these findings, we hypothesize that these differentially expressed proteins likely play a pivotal role in determining the course of infection.
Few studies have examined the cellular immune response of ticks, and further research on the characterization of the hemocytes of ticks is required, particularly on those of Rhipicephalus sanguineus ...(Latreille) because of the medical and veterinary importance of this tick. The aims of this study were to characterize the morphology and the ultrastructure of the different types of hemocytes of adult R. sanguineus and to determine the population abundance and the ultrastructural changes in the hemocytes of ticks infected with Leishmania infantum. The hemocytes were characterized through light and transmission electron microscopy. Within the variability of circulating cells in the hemolymph of adult R. sanguineus, five cell types were identified, which were the prohemocytes, plasmatocytes, granulocytes, spherulocytes, and adipohemocytes. The prohemocytes were the smallest cells found in the hemolymph. The plasmatocytes had polymorphic morphology with vesicles and cytoplasmic projections. The granulocytes had an elliptical shape with the cytoplasm filled with granules of different sizes and electrodensities. The spherulocytes were characterized by several spherules of uniform shapes and sizes that filled the entire cytoplasm, whereas the adipohemocytes had an irregular shape with multiple lipid inclusions that occupied almost the entire cytoplasmic space. The total counts of the hemocyte population increased in the group that was infected with L. infantum. Among the different cell types, the numbers increased and the ultrastructural changes occurred in the granulocytes and the plasmatocytes in the infected group of ticks.
The evaluation of the nutritional value and parameters of ruminal fermentation of tropical forages is important, aiming at its efficient use in ruminant feeding. This study was developed to evaluate ...the forage accumulation, chemical composition, protodioscin content, digestibility, and in vitro degradation kinetics of different Brachiaria spp. cultivars in different evaluation periods. The research was carried out in the semi-arid region of Brazil, from April 2016 to April 2017. The experiment was laid out as a split-plot arrangement in a randomized block design in which five cultivars (B. decumbens cv. Basilisk, and B. brizantha cvs. Marandu, Paiaguás, Piatã, and Xaraés) represented the plot and four evaluation periods (establishment, transition, dry, and rainy) the subplot. There was a cultivar × period interaction effect for forage accumulation rate (FAR), for which cv. Xaraés showed the highest mean (54.1 kg/ha.day DM) in the rainy season. The lowest yield was found in cv. Paiaguás in the dry season (24.1 kg/ha.day DM). Cultivars Basilisk, Marandu, and Paiaguás had the highest crude protein content. The highest in vitro dry matter digestibility values were found in cv. Basilisk in the dry, transition, and rainy periods; cv. Marandu in the transition period, and cvs. Paiaguás and Piatã in their establishment. A correlation was found between the parameters of in vitro degradation kinetics and chemical composition. The protodioscin content was highest in cv. Basilisk, during its establishment (5.5 g/kg DM). Cultivars Paiaguás, Piatã, and Xaraés showed low protodioscin values (<1.0 g/kg DM). Cultivars Basilisk, Marandu, Paiaguás, Piatã, and Xaraés can be used as forage options in the semi-arid environment, as their forage accumulation potential and nutritional value are suitable for animal production even in periods of lower water availability.
This study was conducted to examine the forage production potential and quality of Panicum maximum cultivars in a semi-arid environment, in four different periods. Six cultivars were evaluated: ...Aruana, Massai, Mombasa, BRS Tamani, Tanzania, and BRS Zuri. The experiment was laid out in a randomized-block design with four replicates, and assessments took place in four different periods (establishment, dry season, transition, and rainy season). Forage accumulation rate (FAR), chemical composition, digestibility, and in vitro rumen degradation kinetics were evaluated. There was an interaction effect between cultivars and evaluation periods for all variables, except dry matter (DM) content. The highest FAR occurred in cvs. BRS Tamani (47.0 kg DM/ha/day) and BRS Zuri (86.9 kg DM/ha/day) in the establishment and rainy periods, respectively, while cv. Aruana showed the lowest FAR (14.5 kg DM/ha/day). The highest crude protein contents were found in cv. BRS Tamani in the transition period; cv. BRS Zuri in the dry season; and cv. Tanzania in the rainy season (128.2, 116.7, and 95.0 g/kg DM, respectively). Cultivar Aruana showed the highest average in vitro dry matter digestibility (810.0 g/kg DM). Cultivars Aruana and Zuri exhibited the highest means of the total in vitro gas production (23.59 and 20.24 mL/100 mg DM, respectively). Cultivars BRS Tamani and BRS Zuri had the best response in terms of forage accumulation and nutritional value. The quality of cv. Massai remained constant throughout the year. All Panicum maximum cultivars evaluated here have the potential for use in animal production systems in a semi-arid environment.
The anti-inflammatory effect of physalin E, a seco-steroid isolated from
Physalis angulata L. was evaluated on acute and chronic models of dermatitis induced by 12-O-tetradecanoyl-phorbol-13-acetate ...(TPA) and oxazolone, respectively, in mouse ear. The changes in ear edema/thickness, production of pro-inflammatory cytokines (TNF-α and IFN-γ), myeloperoxidase (MPO) activity, and histological and immunohistochemical findings were analysed, as indicators of dermal inflammation. Similar to dexamethasone, topically applied Physalin E (0.125; 0.25 and 0.5
mg/ear) potently inhibited the TPA and oxazolone-induced dermatitis, leading to substantial reductions in ear edema/thickness, pro-inflammatory cytokines, and MPO activity. These effects were reversed by mifepristone, a steroid antagonist and confirmed by immunohistochemical and histopathological analysis. The data suggest that physalin E may be a potent and topically effective anti-inflammatory agent useful to treat the acute and chronic skin inflammatory conditions.
Parrotfishes contribute to important reef processes through their feeding. Individuals may join groups with distinctive social behavior, with unknown implications for their feeding ecology and, ...ultimately, their functional roles in reef systems. Using
Scarus iseri
populations in Isla Colón, Panama, we investigated whether individuals belonging to the two main social groups formed by this species (‘Territorial’ and ‘Stationary’ groups) differed in their feeding preferences. Territorial groups had access to a diversity of potential food sources, yet showed selectivity for feeding on sandy substrate. Stationary groups showed high selectivity for filamentous algae, despite this resource being less available for this group than for territorial individuals. Initial phase fish had higher bite rates on plants than terminal phase individuals, while the latter had higher bite rates on soft substrata and sponges, both indicating detritus consumption. Parrotfish sociobiology may therefore influence their relative ecosystem impact, with territorial and terminal individuals in both social groups more involved in the detrital food web and stationary groups contributing to a greater extent on algal removal.
For many years, nitric oxide (NO) has been studied as an important mediator in the control of vascular tone. Endothelial deficiencies that diminish NO production can result in the development of ...several future cardiovascular diseases, such as hypertension and arteriosclerosis. In this context, new drugs with potential ability to donate NO have been studied. In this study, 3 aromatic oximes benzophenone oxime, 4-Cl-benzophenone oxime, and E-cinnamaldehyde oxime (E-CAOx) induced vasorelaxation in endothelium-denuded and intact superior mesenteric rings precontracted with phenylephrine. E-CAOx demonstrated the most potent effect, and its mechanism of action was evaluated. Vascular reactivity experiments demonstrated that the effect of E-CAOx was reduced by the presence of 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, 1H1,2,4,oxadiazolo4,3-aquinoxalin-1-one, and (Rp)-8-(para-chlorophenylthio)guanosine-3′,5′-cyclic monophosphorothioate, suggesting the participation of NO/sGC/PKG pathway. NO donation seems to be mediated through nicatinamide adenine dinucleotide phosphate-dependent reductases because 7-ethoxyresorufin decreased the effect of E-CAOx on vascular reactivity and reduced NO formation as detected by flow cytometry using the NO indicator diaminofluorescein 4,5-diacetate. Further downstream of NO donation, K subtype channels were also shown to be involved in the E-CAOx vasorelaxant effect. The present study showed that E-CAOx acts like an NO donor, activating NO/sGC/PKG pathway and thus K channels.
Forests represent an important role in the control of atmospheric emissions through carbon capture. However, in forest fires, the carbon stored during photosynthesis is released into the atmosphere. ...The carbon quantification, in forest burning, is important for the development of measures for its control. The aim of this study was to quantify CO2 and CO emissions of forest fires in Western Amazonia. In this paper, results are described of forest fire experiments conducted in Cruzeiro do Sul and Rio Branco, state of Acre, and Candeias do Jamari, state of Rondônia, Brazil. These cities are located in the Western portion of the Brazilian Amazon region. The biomass content per hectare, in the virgin forest, was measured by indirect methods using formulas with parameters of forest inventories in the central hectare of the test site. The combustion completeness was estimated by randomly selecting 10% of the total logs and twelve 2 × 2 m2 areas along three transects and examining their consumption rates by the fire. The logs were used to determine the combustion completeness of the larger materials (characteristic diameters larger than 10 cm) and the 2 × 2 m2 areas to determine the combustion completeness of small-size materials (those with characteristic diameters lower than 10 cm) and the. The overall biomass consumption by fire was estimated to be 40.0%, 41.2% and 26.2%, in Cruzeiro do Sul, Rio Branco and Candeias do Jamari, respectively. Considering that the combustion gases of carbon in open fires contain approximately 90.0% of CO2 and 10.0% of CO in volumetric basis, the average emission rates of these gases by the burning process, in the three sites, were estimated as 191 ± 46.7 t ha−1 and 13.5 ± 3.3 t ha−1, respectively.
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•Carbon emission of a major Amazonian forest fire experiments.•Biomass consumption of different biomass size materials.•Biomass consumption as function of deforested area.
: Rotundifolone is the major constituent of the essential oil of Mentha x villosa Hudson. In preliminary studies, rotundifolone induced significant hypotensive, bradycardic and vasorelaxant effects ...in rats. Thus, to gain more insight into the pharmacology of rotundifolone, the aim of this study was to characterize the molecular mechanism of action involved in relaxation produced by rotundifolone. The relaxant effect was investigated in rat superior mesenteric arteries by using isometric tension measurements and whole‐cell patch‐clamp techniques. Rotundifolone relaxed phenylephrine‐induced contractions in a concentration‐dependent manner. Pre‐treatment with KCl (20 mM), charybdotoxin (10−7 M) or tetraethylammonium (TEA 10−3 or 3 × 10−3 M) significantly attenuated the relaxation effect induced by rotundifolone. Additionally, whole‐cell patch‐clamp recordings were made in mesenteric smooth muscle cells and showed that rotundifolone significantly increased K+ currents, and this effect was abolished by TEA (10−3 M), suggesting the participation of BKCa channels. Furthermore, rotundifolone inhibited the vasoconstriction induced by CaCl2 in depolarizing nominally Ca2+‐free medium and antagonized the contractions elicited by an L‐type Ca2+ channel agonist, S(‐)‐Bay K 8644 (2 × 10−7 M), indicating that the vasodilatation involved inhibition of Ca2+ influx through L‐type voltage‐dependent calcium channels (Cav type‐L). Additionally, rotundifolone inhibited L‐type Ca2+ currents (ICaL), affecting the voltage‐dependent activation of ICaL and steady‐state inactivation. Our findings suggest that rotundifolone induces vasodilatation through two distinct but complementary mechanisms that clearly depend on the concentration range used. Rotundifolone elicits an increase in the current density of BKCa channels and causes a shift in the steady‐state inactivation relationship for Cav type‐L towards more hyperpolarized membrane potentials.
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