245 research outputs found

    Byrsonima Crassa Niedenzu (ik): Antimicrobial Activity And Chemical Study

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    The methanolic extract of leaves from Byrsonima crassa, a Brazilian medicinal plant, was analyzed by CC and HPLC. Four constituents were isolated and identified as quercetin, methyl gallate, (-)-epigallocatechin gallate and quercetin-3-O-(2″-galloyl)-α-L-arabinopyranoside. The methanolic and hydromethanolic extract, as well as fractions, were evaluated regarding their possible antimicrobial activity using in vitro methods. Results showed that both extracts and fractions exhibited significant antimicrobial activity against all tested strains.2617175Agrawal, P.K., (1989) Carbon 13NMR of Flavonoids, , Amsterdam:ElsevierAlzoreky, N.S., Nakahara, K., Antibacterial activity of extracts from some edible plants commonly consumed in Asia (2003) Int J Food Microbiol, 80, pp. 223-230Amarqiuise, A., Che, C.T., Bejar, E., Malone, M.H., Fong, H.H.S., A New Glycolipid from Byrsonima crassifolia (1994) Planta Med, 60, pp. 85-86Basile, A., Sorbo, S., Giordano, S., Ricciardi, L., Ferrara, S., Montesano, D., Cobianchi, R.C., Ferrara, L., Antibacterial and allelopathic activity of extract from Castanea sativa leaves (2000) Fitoterapia, 71, pp. S110-S116Bauer, A.W., Kirby, M.D.K., Sherries, J.C., Truck, M., Antibiotic susceptibilities testing by standard single disc diffusion method (1966) Am J Clin Pathol, 45, pp. 493-496Bejar, E., Amarquaye, A., Che, C.T., Malone, M.H., Fong, H.H.S., Constituents of Byrsonima crassifolia and their spasmogenic activity (1995) Int J Pharmacog, 33, pp. 25-32Binutu, O.A., Cordell, G.A., Gallic acid derivatives from Mezoneuron benthamianum leaves (2000) Pharm Biol, 38, pp. 284-286Djipa, C.D., Delmee, M., Quetin-Leclercq, J., Antimicrobial activity of bark extracts of Syzygium jambos (L.) Alston (Myrtaceae) (2000) J Ethnopharmacol, 71, pp. 307-313Geiss, F., Heinrich, M., Hunkler, D., Rimpler, H., Heinrich, M., Proanthocyanidins with (+)-epicatechin units from Byrsonima crassifolia bark (1995) Phytochemistry, 39, pp. 635-643Gottlieb, O.R., Henriques Mendes, P., Taveira Magalhães, M., Triterpenoids from Byrsonima verbascifolia (1975) Phytochemistry, 14, pp. 1456-1456Harborne, J.B., (1996) The Flavonoids: Advances in Research since 1986, , New York:Chapman & HallLopez, A., Hudson, J.B., Towers, G.H.N., Antiviral and antimicrobial activities of Colombian medicinal plants (2001) J Ethnopharmacol, 77, pp. 189-196Martínez-Vasquéz, M., González-Esquinca, A.R., Cazares Luna, L., Moreno Gutiérrez, M.N., García-Argáez, A.N., Antimicrobial activity of Byrsonima crassifolia (L.) H.B.K (1999) J Ethnopharmacol, 66, pp. 79-82Mendes, C.C., Cruz, F.G., David, J.M., Nascimento, I.P., David, J.P., Triterpenes esterified with fatty acid and triterpene acids isolated from Byrsonima microphylla (1999) Quím Nova, 22, pp. 185-188Nascimento, G.G.F., Locatelli, J., Freitas, P.C., Silva, G.L., Antibacterial activity of plants extracts and phytochemicals on antibiotic-resistant bacteria (2000) Braz J Microbiol, 31, pp. 247-256(2003) Performance Standards for Antimicrobial Disc Susceptibility Tests, , Approved Standard M2-A7, Pennsylvania:WaynePenna, C., Marino, S., Vivot, E., Cruanes, M.C., Munoz, J.D., Cruanes, J., Ferraro, G., Martino, V., Antimicrobial activity of Argentine plants used in the treatment of infectious diseases. Isolation of active compounds from Sebastiania brasiliensis (2001) J Ethnopharmacol, 77, pp. 37-40Pretorius, J.C., Magama, S., Zietsman, P.C., Purification and identification of antibacterial compounds from Euclea crispa subsp crispa (Ebenaceae) leaves (2003) S Afr J Bot, 69, pp. 579-586Rastrelli, L., De Tommasi, N., Berger, I., Caceres, A., Saravia, A., De Simone, F., Glycolipids from Byrsonima crassifolia (1997) Phytochemistry, 45, pp. 647-650Sannomiya, M., Rodrigues, C.M., Coelho, R.G., Santos, L.C., Hiruma-Lima, C.A., Souza Brito, A.R.M., Vilegas, W., Application of preparative high-speed counter-current chromatography for the separation of flavonoids from the leaves of Byrsonima crassa Niedenzu (IK) (2004) J Chromatogr A, 1035, pp. 47-51Sannomiya, M., Fonseca, V.B., Da Silva, M.A., Rocha, L.R.M., Dos Santos, L.C., Souza, H.C.A., Brito, A.R.M., Vilegas, W., Flavonoids and antiulcerogenic activity from Byrsonima crassa leaves extracts (2005) J Ethnopharmacol, 97, pp. 1-6Silva, S.R., Silva, A.P., Munhoz, C.B., Silva Jr., M.C., Medeiros, M.B., (2001) Guia de Plantas Do Cerrado Utilizadas Na Chapada Dos Veadeiros, , Brasília:WWF58pSrinivasan, D., Nathan, S., Suresh, T., Perumalsamy, P.L., Antimicrobial activity of certain Indian medicinal plants used in folkloric medicine (2001) J Ethnopharmacol, 74, pp. 217-220Wagner, H., Bladt, H., Zgainski, E.M., (1984) Plant Drug Analysis, , Berlin:Springer320

    Exploring antifungal potential: the flavonoid composition of Machaerium villosum extracts against Cryptococcus neoformans.

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    The objective of this study was, therefore, to conduct a chemical analysis and assess the biological potential of the hydroethanolic extract obtained from the leaves of Machaerium villosum. Thus, this study investigates the extract from this plant, which belongs to the Fabaceae family, known for its rich flavonoid content

    Mapping localized surface plasmons within silver nanocubes using cathodoluminescence hyperspectral imaging

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    Localized surface plasmons within silver nanocubes less than 50 nm in size are investigated using high resolution cathodoluminescence hyperspectral imaging. Multivariate statistical analysis of the multidimensional luminescence dataset allows both the identification of distinct spectral features in the emission and the mapping of their spatial distribution. These results show a 490 nm peak emitted from the cube faces, with shorter wavelength luminescence coming from the vertices and edges; this provides direct experimental confirmation of theoretical predictions

    Insulin modulates cytokine release and selectin expression in the early phase of allergic airway inflammation in diabetic rats

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    <p>Abstract</p> <p>Background</p> <p>Clinical and experimental data suggest that the inflammatory response is impaired in diabetics and can be modulated by insulin. The present study was undertaken to investigate the role of insulin on the early phase of allergic airway inflammation.</p> <p>Methods</p> <p>Diabetic male Wistar rats (alloxan, 42 mg/Kg, i.v., 10 days) and controls were sensitized by s.c. injection of ovalbumin (OA) in aluminium hydroxide 14 days before OA (1 mg/0.4 mL) or saline intratracheal challenge. The following analyses were performed 6 hours thereafter: a) quantification of interleukin (IL)-1β, tumor necrosis factor (TNF)-α and cytokine-induced neutrophil chemoattractant (CINC)-1 in the bronchoalveolar lavage fluid (BALF) by Enzyme-Linked Immunosorbent Assay, b) expression of E- and P- selectins on lung vessels by immunohistochemistry, and c) inflammatory cell infiltration into the airways and lung parenchyma. NPH insulin (4 IU, s.c.) was given i.v. 2 hours before antigen challenge.</p> <p>Results</p> <p>Diabetic rats exhibited significant reduction in the BALF concentrations of IL-1β (30%) and TNF-α (45%), and in the lung expression of P-selectin (30%) compared to non-diabetic animals. This was accompanied by reduced number of neutrophils into the airways and around bronchi and blood vessels. There were no differences in the CINC-1 levels in BALF, and E-selectin expression. Treatment of diabetic rats with NPH insulin, 2 hours before antigen challenge, restored the reduced levels of IL-1β, TNF-α and P-selectin, and neutrophil migration.</p> <p>Conclusion</p> <p>Data presented suggest that insulin modulates the production/release of TNF-α and IL-1β, the expression of P- and E-selectin, and the associated neutrophil migration into the lungs during the early phase of the allergic inflammatory reaction.</p

    Anti-Helicobacter pylori activity and immunostimulatory effect of extracts from Byrsonima crassa Nied. (Malpighiaceae)

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    <p>Abstract</p> <p>Background</p> <p>Several <it>in vitro </it>studies have looked at the effect of medicinal plant extracts against <it>Helicobacter pylori </it>(<it>H. pylori</it>). Regardless of the popular use of <it>Byrsonima crassa </it>(<it>B. crassa</it>) as antiemetic, diuretic, febrifuge, to treat diarrhea, gastritis and ulcers, there is no data on its effects against <it>H. pylori</it>. In this study, we evaluated the anti-<it>H. pylori </it>of <it>B. crassa </it>leaves extracts and its effects on reactive oxygen/nitrogen intermediates induction by murine peritoneal macrophages.</p> <p>Methods</p> <p>The minimal inhibitory concentration (MIC) was determined by broth microdilution method and the production of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) and nitric oxide (NO) by the horseradish peroxidase-dependent oxidation of phenol red and Griess reaction, respectively.</p> <p>Results</p> <p>The methanolic (MeOH) and chloroformic (CHCl<sub>3</sub>) extracts inhibit, <it>in vitro</it>, the growth of <it>H. pylori </it>with MIC value of 1024 μg/ml. The MeOH extract induced the production H<sub>2</sub>O<sub>2 </sub>and NO, but CHCl<sub>3 </sub>extract only NO.</p> <p>Conclusion</p> <p>Based in our results, <it>B. crassa </it>can be considered a source of compounds with anti-<it>H. pylori </it>activity, but its use should be done with caution in treatment of the gastritis and peptic ulcers, since the reactive oxygen/nitrogen intermediates are involved in the pathogenesis of gastric mucosal injury induced by ulcerogenic agents and <it>H. pylori </it>infections.</p

    Optical detection of single non-absorbing molecules using the surface plasmon of a gold nanorod

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    Current optical detection schemes for single molecules require light absorption, either to produce fluorescence or direct absorption signals. This severely limits the range of molecules that can be detected, because most molecules are purely refractive. Metal nanoparticles or dielectric resonators detect non-absorbing molecules by a resonance shift in response to a local perturbation of the refractive index, but neither has reached single-protein sensitivity. The most sensitive plasmon sensors to date detect single molecules only when the plasmon shift is amplified by a highly polarizable label or by a localized precipitation reaction on the particle's surface. Without amplification, the sensitivity only allows for the statistical detection of single molecules. Here we demonstrate plasmonic detection of single molecules in realtime, without the need for labeling or amplification. We monitor the plasmon resonance of a single gold nanorod with a sensitive photothermal assay and achieve a ~ 700-fold increase in sensitivity compared to state-of-the-art plasmon sensors. We find that the sensitivity of the sensor is intrinsically limited due to spectral diffusion of the SPR. We believe this is the first optical technique that detects single molecules purely by their refractive index, without any need for photon absorption by the molecule. The small size, bio-compatibility and straightforward surface chemistry of gold nanorods may open the way to the selective and local detection of purely refractive proteins in live cells

    New flavone from the leaves of Neea theifera (Nyctaginaceae)

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    Neea theifera Oerst. (Nyctaginaceae) is widely used in Brazilian folk medicine for the treatment of gastric ulcers and inflammation. Phytochemical investigation of the leaves of Neea theifera afforded the isolation of the new flavone luteolin-7-O-[2″-O-(5‴-O-feruloyl)-β-D-apiofuranosyl]- β-D-glucopyranoside (1) besides the eight-known compounds vitexin, isovitexin, isoorientin, orientin, vicenin-2, chrysoeriol, apigenin and luteolin. Their chemical identification was established by NMR spectroscopic methods including 2D-NMR, as well as UV and ESI-MS analyses. ©2007 Sociedade Brasileira de Química

    Antimicrobial activity of Byrsonima species (Malpighiaceae)

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Byrsonima species, family Malpighiaceae, is popularly known as 'murici'. There are several properties attributed to the leaves of Byrsonima species including febrifuge, to treat gastrointestinal dysfunctions and skin diseases. In this work, the antimicrobial activity of Byrsonima fagifolia, B. basiloba and B. intermedia extracts obtained from the leaves were evaluated by using the disc-diffusion method. The results obtained showed that the methanol extracts of leaves had presented antimicrobial activity against all the microorganisms tested.18690695Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Breast-Lesion Characterization using Textural Features of Quantitative Ultrasound Parametric Maps

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    © 2017 The Author(s). This study evaluated, for the first time, the efficacy of quantitative ultrasound (QUS) spectral parametric maps in conjunction with texture-analysis techniques to differentiate non-invasively benign versus malignant breast lesions. Ultrasound B-mode images and radiofrequency data were acquired from 78 patients with suspicious breast lesions. QUS spectral-analysis techniques were performed on radiofrequency data to generate parametric maps of mid-band fit, spectral slope, spectral intercept, spacing among scatterers, average scatterer diameter, and average acoustic concentration. Texture-analysis techniques were applied to determine imaging biomarkers consisting of mean, contrast, correlation, energy and homogeneity features of parametric maps. These biomarkers were utilized to classify benign versus malignant lesions with leave-one-patient-out cross-validation. Results were compared to histopathology findings from biopsy specimens and radiology reports on MR images to evaluate the accuracy of technique. Among the biomarkers investigated, one mean-value parameter and 14 textural features demonstrated statistically significant differences (p < 0.05) between the two lesion types. A hybrid biomarker developed using a stepwise feature selection method could classify the legions with a sensitivity of 96%, a specificity of 84%, and an AUC of 0.97. Findings from this study pave the way towards adapting novel QUS-based frameworks for breast cancer screening and rapid diagnosis in clinic
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