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Com a grande preocupação pela saúde e a preservação do meio ambiente, a busca por fontes alternativas de controle de doenças vem crescendo na agricultura. Isso porque os agrotóxicos estão sendo usados de forma indiscriminada, colocando em risco a saúde humana e o meio ambiente. As recentes pesquisas mostram a variedade de extratos vegetais que possuem substâncias bioativas eficientes no controle de patógenos. Por este motivo, o presente trabalho teve por objetivo avaliar o efeito de extrato de própolis e Plecthanthus amboinicus no tratamento de sementes de cebola inoculadas com Aspergillus sp. As sementes de cebola foram inoculadas com o fungo Aspergillus flavus. Posteriormente foram aplicados os tratamentos com agitação de cinco minutos em soluções de própolis e P. amboinicus nas concentrações: 0; 5; 15; 25%. O experimento foi montado em esquema fatorial 2 x 4 em delineamento inteiramente casualizado com cinco repetições. Para as soluções de P. amboinicus houve o preparo de meios de cultura com BDA (batata-dextrose-ágar) e inseridos discos de 5 mm do fungo, para que houvesse a verificação do efeito in vitro no desenvolvimento do patógeno. As características avaliadas foram: diâmetro do halo de crescimento do fungo (teste in vitro); teste de sanidade; primeira contagem de germinação; germinação ; massa seca de plântula; comprimento de raiz e parte aérea de plântula e teste de emergência. Os extratos de hortelã-pimenta e de própolis não foram eficientes no controle do fungo Aspergillus sp., mediante as concentrações de estudo. O extrato de hortelã-pimenta utilizado no tratamento de sementes de cebola pode ter provocado fitotoxidez, desencadeado menores valores para a maioria das características de qualidade fisiológica destas sementes, comparativamente ao extrato de própolis.

The implant indication of cardiac electronic devices continues to expand; therefore, we have observed increasing complications related to their removal. We describe the case of a patient who presented with prolonged bloodstream infection after having undergone removal of a pacemaker. After extensive workup for fever of unknown origin and antibiotic therapy without any improvement, it was possible to demonstrate a foreign body in the right subclavian vein and superior vena cava corresponding to the distal part of the right ventricular lead. Endovascular removal of the foreign body and prolonged antibiotic administration was followed by complete resolution of the clinical picture. We ascribed the difficulty in diagnosing the source of the infection especially to the lack of local manifestations.

Although conceptually very simple, the statistical mechanics of surfactant monolayers in solution give rise to the rich phase behavior and novel physical properties of these systems. The fluctuations due to capillary waves of a single saturated monolayer are studied using X-ray reflectivity. The interfacial tension and bending rigidity are found to be very small and account for the disordered structure of bicontinuous microemulsions. Neutron scattering techniques are also used to measure the decay of structural correlations among the surfactant monolayers within a microemulsion phase, and these results are explained using a Ginzburg—Landau theory.

The use of X-ray and neutron reflectivity measurements to determine the density profile across and interface or across thin films has become increasingly popular over the last few years. However, in general convenient model-independent methods of inverting the reflectivity profiles to obtain the density profile have been missing. We present here one such approach using the method of anomalous reflectivity from the substrate and demonstrate its applicability in the case of an organic thin film.

We present a new method for obtaining the scattering length density (sld) profile perpendicular to a uniform, smooth surface which is consistent with the measured reflectivity over a finite Q range. The method is applicable to a free liquid surface as well as a thin film deposited on a known substrate. As an illustration, we apply the method to obtain: degree of ordering of an intact Langmuir-Blodgett film on a silicon substrate; surface-induced layering of water and oil in bicontinuous microemulsions; and segregation of polymers near air-film and the film-substrate interfaces.

We evaluated the effect of the nonpeptide mimic of angiotensin (Ang)-(1-7), AVE 0991, on the hypotensive effect of bradykinin (BK). Increasing doses of intra-arterial or intravenous BK were administered before and 30 minutes after the beginning of AVE 0991 infusion. The effect of AVE 0991 on plasma Ang-converting enzyme activity was tested using Hip-His-Leu as the substrate. The interaction of AVE 0991 with Ang-converting enzyme in vivo was tested by determining its effect on the pressor action of Ang I or Ang II. AVE 0991 produced a significant and similar potentiation of intra-arterial or intravenous bradykinin. AVE 0991 did not inhibit plasma Ang-converting enzyme activity in vitro or the pressor effect of Ang I in vivo. N W -nitro- l -arginine methyl ester or D-Ala 7 -Ang-(1-7) administration abolished the BK potentiating effect of AVE 0991. We further examined the BK-potentiating effect of AVE 0991, evaluating its effect on NO production in rabbit endothelial cells. The NO release was measured using the 4-amino-5-methylamino-2′-7′-difluorofluorescein diacetate. A synergistic effect of AVE 0991 and BK on NO release was observed. These results suggest that AVE 0991 potentiates bradykinin through an Ang-converting enzyme–independent, NO-dependent receptor Mas-mediated mechanism. This effect may contribute to the improvement of endothelial function by AVE 0991 in vivo.

CGEN-856S is a novel Mas agonist. Herein, we examined the effects of this peptide on isoproterenol (ISO)-induced cardiac remodeling and myocardial infarction (MI) injury. We also sought to determine whether CGEN-856S activates the underlying mechanisms related to Mas receptor activation. Heart hypertrophy and fibrosis were induced by ISO (2 mg·kg(-1)·day(-1)) in Wistar rats. After a 7-day treatment period with CGEN-856S (90 µg·kg(-1)·day(-1)) or vehicle, the cardiomyocyte diameter was evaluated in left ventricular sections stained with hematoxylin and eosin, and immunofluorescence labeling and quantitative confocal microscopy were used to quantify the deposition of type I and III collagen and fibronectin in the left ventricles. MI was induced by coronary artery ligation, and CGEN-856S (90 µg·kg(-1)·day(-1)) or saline was administered for 14 days. The Langendorff technique was used to evaluate cardiac function, and left ventricular sections were stained with Masson's trichrome dye to quantify the infarct area. Using Chinese hamster ovary cells stably transfected with Mas cDNA, we evaluated whether CGEN-856S alters AKT and endothelial nitric oxide synthase (eNOS) phosphorylation. CGEN-856S reduced the degree of ISO-induced hypertrophy (13.91±0.17 µm vs. 12.41±0.16 µm in the ISO+CGEN-856S group). In addition, the Mas agonist attenuated the ISO-induced increase in collagen I, collagen III, and fibronectin deposition. CGEN-856S markedly attenuated the MI-induced decrease in systolic tension, as well as in +dT/dt and -dT/dt. Furthermore, CGEN-856S administration significantly decreased the infarct area (23.68±2.78% vs. 13.95±4.37% in the MI+CGEN-856S group). These effects likely involved the participation of AKT and NO, as CGEN-856S administration increased the levels of p-AKT and p-eNOS. Thus, our results indicate that CGEN-856S exerts cardioprotective effects on ISO-induced cardiac remodeling and MI-mediated heart failure in rats through a mechanism likely involving the eNOS/AKT pathway.

The roughness and surface correlations of a surfactant monolayer at an oil-water interface in equilibrium with a small amount of middle-phase microemulsion were studied using x-ray scattering. High energy x rays in conjunction with tight instrumental resolution allow us to separate and quantify the specular reflectivity and surface diffuse scattering of the interface. The experimental results are explained using a height-height correlation function derived from a capillary wave model. The interface was found to have an intrinsic roughness of 85 \AA{} and an interfacial tension of 0.11 dyn/cm.

We expand an accurate, closed-form equation for the reflectivity in a power series around [ital q][sub 2]=0, where [ital q][sub 2] is the [ital z] component of the wave-vector transfer in a film of constant composition. We examine, in particular, the case where [ital q][sub 2]=0 at the critical edge. Such an example might be realized through a neutron-reflectivity experiment on a microemulsion that exhibits surface layering. We find the coefficients of this low-wave-vector expansion to be the moments of the scattering-length density profile. We demonstrate how the first moment of the profile can be obtained from an accurate reflectivity measurement.