Prevalence of Enterococcus spp. isolated from free-range chickens in different regions of Distrito Federal, Brazil

It was studied whether vancomycin-resistant enterococci (VRE) colonize poultry raised without receiving antimicrobial growth promoters (AGP), in non-intensive production systems. A total of 200 cloacal swabs were colleted in farms (n=40) of eight different regions of the Distrito Federal. After selective isolation, the typical enterococcal colonies were submitted to the multiplex PCR to identify enterococcal species (E. faecalis, E. faecium, E. gallinarum, and E. casseliflavus), and genes coding for high-level vancomycin resistance phenotypes. No VRE were found in the examined samples. The prevalence rates were higher for E. gallinarum (n=26; 13.0%) and E. casseliflavus (n=11; 5.5%). It was found remarkable differences in the prevalence of E. gallinarum and E. casseliflavus among the poultry farms and studied regions, and it seems that poultry raised in non-intensive production systems in the Distrito Federal of Brazil are not reservoirs of VRE

Quantum Confinement Effects On The Phonons Of Pbte Quantum Dots In Tellurite Glasses

We present Raman-scattering results for PbTe quantum dots (QDs) in doped telluride glasses which clearly show the confinement effects on the phonon spectra as a function of the quantum-dot size..6892Kraus and F. Wise;Phys. Rev. Lett. 79 (25), 5102-05 (1997)Thoen, E.R., (1998) Appl, Phys. Lett, 73 (15), p. 2149Wise, F., (2000) Ace. Chem. Res, 33, pp. 773-780Tsuda, S., Cruz, C.H.B., (1991) Opt. Lett, 16, p. 1596Nakamura, A., Tokizaki, T., Akiyama, H., Kataoka, T., (1992) J. Lumin, 53, p. 105Ohtsuka, S., Koyama, T., Tsunetomo, K., Nagata, H., Tanaka, S., (1992) Appl. Phys. Lett, 61, p. 2953Tsunetomo, K., Ohtsuka, S., Koyama, T., Tanaka, S., Sasaki, F., Kobayashi, S., (1995) Nonlin. Opt, 13, p. 109Colvin, V.L., Schlamp, M.C., Alivisatos, A.P., (1995) Nature ∼London, 370, p. 354Dabbousi, M., Bawendi, G., Onitsuka, O., Rubner, M.F., (1995) Appl. Phys. Lett, 66, p. 1316Guerreiro, T., Ten, S., Borrelli, N.F., Butty, J., Jabbour, G.E., Peyghambarian, N., (1997) Appl. Phys. Lett, 71, p. 1595Murray, C.B., Kagan, C.R., Bawendi, M.G., (1995) Science, 270, p. 1335Kang, I., Wise, F.W., (1997) J. Opt. Soc. Am. B, 14, p. 1632Reynoso, V.C.S., de Paula, A.M., Cuevas, R.F., Medeiros Neto, J.A., Alves, O.L., Cesar, C.L., Barbosa, L.C., (1995) Electron. Lett, 31, p. 1013G.J.Jacob, C.L.Cesar,L.C.Barbosa, Chem.Phys.Glass 43C (2002)250-252Esch, V., Fluegel, B., Khitrova, G., Gibbs, H.M., Jiajin, X., Kang, K., Koch, S.W., Peyghambarian, N., (1990) Phys. Rev, B42, p. 7450Sercel, P.C., Valhala, K.J., (1990) Phys. Rev, B42, p. 3690Schoenlein, R.W., Mittleman, D.M., Shiang, J.J., Alivisatos, A.P., Shank, C.V., (1993) Phys. Rev. Lett, 70, p. 1014Ekimov, A.I., Hache, F., Schanne-Klein, M.C., Ricard, D., Flytzanis, C., Kudryavtsev, I.A., Yazeva, T.V., Efros, A.L., (1993) J. Opt. Soc. Am, B10, p. 100Norris, D.J., Sacra, A., Bawendi, C.B.M.M.G., (1994) Phys. Rev. Lett, 72, p. 2612de Oliveira, C.R.M., de Paula, A.M., Filho, F.O.P., Neto, J.A.M., Barbosa, L.C., Alves, O.L., Menezes, E.A., Cesar, C.L., (1995) Appl. Phys. Lett, 66, p. 439R. Ruppin and R. Englman, Rep. Prog. Phys. 33, 149 (1970)R. Ruppin, J. Phys. C: 8, 1969 (1975)Thoen, E.R., Steinmeyer, G., Langlois, P., Ippen, E.P., Tudury, G.E., Brito Cruz, C.H., Barbosa, L.C., Cesar, C.L., (1998) Appl. Phys. Lett, 73Krauss, T.D., Wise, F.W., Coherent and Acoustical Phonon in a Semiconductor Quantum DotsPhis (1997) Rev. Lett, 79, pp. 5102-510

Optical Tweezers 3d Photonic Force Spectroscopy

Since optical tweezers trapped microspheres can be used as an ultrasensitive force measurements technique, the knowledge of its theoretical description is of utmost importance. However, even the description of the incident electromagnetic fields under very tight focusing, typical of the optical trap, is not yet a closed problem. Therefore it is important to experimentally obtain whole accurate curves of the force as a function of wavelength, polarization and incident beam 3D position with respect to the center of the microsphere. Theoretical models for optical forces such as the Generalized Lorenz-Mie theory, can then be applied to the precisely evaluated experimental results. Using a dual trap in an upright standard optical microscope, one to keep the particle at the equilibrium position and the other to disturb it we have been able to obtain these force curves as a function of x, y and z position, incident beam polarization and also wavelength. Further investigation of optical forces was conducted for wavelengths in and out Mie resonances of the dielectric microspherical cavities for both TM and TE modes.6131Ashkin, A., Dziedzic, J.M., Bjorkholm, J.E., Chu, S., Observation of a single-beam gradient force trap for dielectric particles (1986) Opt. Lett., 11, pp. 288-290Ashkin, A., Dziedzic, J.M., Optical trapping and manipulation of viruses and bacteria (1987) Science, 235, pp. 1517-1520Grier, D.G., A revolution in optical manipulation (2003) Nature, 424, pp. 810-816Neuman, K.C., Block, S., Optical trapping (2004) Rev. Sci. Instrum., 75, pp. 2787-2809Lock, J.A., Calculation of the radiation trapping force for laser tweezers by use of generalized Lorenz-Mie theory. I. Localized model description of an on-axis tightly focused laser beam with spherical aberration (2004) Appl. Opt., 43, pp. 2532-2544Lock, J.A., Calculation of the radiation trapping force for laser tweezers by use of generalized Lorenz-Mie theory. II. On-axis trapping force (2004) Appl. Opt., 43, pp. 2545-2554Mazolli, A., Neto, P.A.M., Nussenzveig, H.M., Theory of trapping forces in optical tweezers (2003) Proc. Royal Soc. London Ser. A Math. Phys. Eng. Sci., 459, pp. 3021-3041Fontes, A., Neves, A.A.R., Moreira, W.L., De Thomaz, A.A., Barbosa, L.C., De Paula, A.M., Cesar, C.L., Double optical tweezers for ultrasensitive force spectroscopy in microsphere Mie scattering (2005) Appl. Phys. Lett., 87. , Art. No. 221109Ren, K.F., Gouesbet, G., Gréhan, G., Integral localized approximation in generalized Lorenz-Mie theory (1998) Appl. Opt., 37, pp. 4218-4225Lock, J.A., Excitation efficiency of a morphology-dependent resonance by a focused Gaussian beam (1998) J. Opt. Soc. Am. A, 15, pp. 2986-2994Davis, L.W., Theory of electromagnetic beams (1979) Phys. Rev. A, 19, pp. 1177-1779Ren, K.F., Gréhan, G., Gouesbet, G., Radiation pressure forces exerted on a particle arbitrarily located in a gaussian beam by using the generalized Lorenz-Mie theory and associated resonance effects (1994) Opt. Commun., 108, pp. 343-354Ren, K.F., Gréhan, G., Gouesbet, G., Symmetry relations in generalized Lorenz-Mie theory (1994) J. Opt. Soc. Am. A, 11, pp. 1812-181

Pbte Quantum Dots In Tellurite Glass Microstructured Optical Fiber

PbTe doped tellurite glass photonic optical fiber for non linear application were developed using rod in tube method in a draw tower. We follow the growth kinetics of the quantum dots in the optical fiber by High Resolution Transmission Electron Microscopy giving some results related with the growth kinetic of the same in function of time so much for optical fiber as for the glass bulk. Absorption peak near 1500 nm as observed and it was attributed the optical resonance due PbTe quantum dots in the core fiber.6902Tsunetomo, K., (1995) Nonlinear Opt, 13, p. 109Borrelli, N.F., Smith, D.W., (1994) J. Non-Cryst. Soi, 180, p. 25Lipovskii, A., Kolobkova, E.A., Petrikov, V., Kang, I., Olkhovets, A., Krauus, T., Thomas, M., Kycia, S., (1997) Appl. Phys. Lett, 71, p. 3406Reynoso, V.C.S., de Paula, A.M., Cuevas, R.F., Medeiros Neto, J.A., Alves, O.L., Cesar, C.L., Barbosa, L.C., (1995) Elect. Lett, 31 (12), pp. 1013-1014Rodrigues, E., Jimenez, E., Jacob, G.J., Neves, A.A.A., Cesar, C.L., Barbosa, L.C., (2005) Phisica E, 26, pp. 321-325Jacob, G.J., Cesar, C.L., Barbosa, L.C., Tellurite Glass Doped with PbTe Quantum Dots (2002) Physics and Chemistry of Glass, 43 C, pp. 250-253Jacob, G.J., Rodriguez, E., Barbosa, L.C., Cesar, C.L., Tellurite Glass Optical fiber doped with PbTe Quantum DotsPhotonics West 2005, The International Society for Optical Engineering SPIEEnomoto, Y., Tokuyama, M., Kawasaki, K., (1986) Act. Metall, 34, p. 2139Marqusee, J.A., Ross, J., (1984) J. Chem. Phys, 80, p. 536Lifshitz, E.M., Slyozov, V.V., (1961) J. Phys. Chem. Sol, 19, p. 3

Novel Perspectives in Management of Angiogenesis and Cancer Therapy

Funding: The project was funded by IPOLFG EPE and by iNOVA4Health (UID/Multi/04462/2019) a program financially supported by Fundação para a Ciência e Tecnologia (FCT)/Ministério da Educação e Ciência, through national funds. We also acknowledge funding from FCT-MCTES through the project DREAM—PTDC/MEC-ONC/29327/2017. FL-C PhD fellowship was funded by FCT (PD/BD/128337/2017).The activation of endothelial cells (ECs) is a crucial step on the road map of tumor angiogenesis and expanding evidence indicates that a pro-oxidant tumor microenvironment, conditioned by cancer metabolic rewiring, is a relevant controller of this process. Herein, we investigated the contribution of oxidative stress-induced ferroptosis to ECs activation. Moreover, we also addressed the anti-angiogenic effect of Propranolol. We observed that a ferroptosis-like mechanism, induced by xCT inhibition with Erastin, at a non-lethal level, promoted features of ECs activation, such as proliferation, migration and vessel-like structures formation, concomitantly with the depletion of reduced glutathione (GSH) and increased levels of oxidative stress and lipid peroxides. Additionally, this ferroptosis-like mechanism promoted vascular endothelial cadherin (VE-cadherin) junctional gaps and potentiated cancer cell adhesion to ECs and transendothelial migration. Propranolol was able to revert Erastin-dependent activation of ECs and increased levels of hydrogen sulfide (H2S) underlie the mechanism of action of Propranolol. Furthermore, we tested a dual-effect therapy by promoting ECs stability with Propranolol and boosting oxidative stress to induce cancer cell death with a nanoformulation comprising selenium-containing chrysin (SeChry) encapsulated in a fourth generation polyurea dendrimer (SeChry@PUREG4). Our data showed that novel developments in cancer treatment may rely on multi-targeting strategies focusing on nanoformulations for a safer induction of cancer cell death, taking advantage of tumor vasculature stabilization.publishersversionpublishe

Evidence Of Chemotaxis By Quantitative Measurement Of The Force Vectors Of Trypanossoma Cruzi In The Vicinity Of The Rhodnius Prolixus Midgut Wall Cell

In this work we used a methodology to study chemotaxis of Trypanossoma cruzi (T. Cruzi) in real time using an Optical Tweezers system. Trapped beads were used as a force transducer for measuring forces of the same order of magnitude as typical forces induced by flagellar motion. Optical Tweezers allowed real time measurements of the force vectors, strength and direction, of living parasites under chemical or other kinds of gradients. This seems to be the ideal tool to perform observations of taxis response of cells and microorganisms with high sensitivity to capture instantaneous responses to a given stimulus. We applied this methodology to investigate the T. cruzi under distinct situations: the parasite alone and in the presence of its insect-vector Rhodnius prolixus (R. prolixus). © 2009 SPIE.7400http://www.who.int/tdr/diseases/chagas/diseaseinfo.htmlAnna, B., Carole, A.P., Eukaryotic chemotaxis at a glance (2008) J. Cell Science, 121, pp. 2621-2624Laszlo, K., Chemotaxis: The proper physiological response to evaluate phylogeny of signal molecules (1999) Acta Biol Hung, 50, pp. 375-394Law, A.M.J., Aitken, M.D., Continuous-flow capillary assay for measuring bacterial chemotaxis (2005) Appl. Environ. Microbiol., 71, pp. 3137-3143Khan, S., Jain, S., Reid, G.P., Trentham, D.R., The fast tumble signal in bacterial chemotaxis (2004) Biophys. J., 86, pp. 4049-4058Neuman, K.C., Chadd, E.H., Liou, G.F., Bergman, K., Block, S.M., Characterization of photodamage to escherichia coli in optical traps (1999) Biophys. J., 77, pp. 2856-2863Bleul, C.C., Farzan, M., Choe, H., Parolin, C., Clark-Lewis, I., Sodroski, J., Springer, T.A., The lymphocyte chemoattractant SDF-1 is a ligand for LESTR/fusin and blocks HIV-1 entry (1996) Nature, 382 (6594), pp. 829-833. , DOI 10.1038/382829a0Nagasawa, T., Hirota, S., Tachibana, K., Takakura, N., Nishikawa, S., Kitamura, Y., Yoshida, N., Kishimoto, T., Defects of B-cell lymphopoiesis and bone-marrow myelopoiesis in mice lacking the CXC chemokine PBSF/SDF- 1 (1996) Nature, 382, pp. 635-638Nelson, R.D., Quie, P.G., Simmons, R.L., Spontaneous migration of human polymorphonuclear leukocytes and monocytes, chemotaxis under agarose-new and simple method for measuring chemotaxis and (1975) J. Immunol., 115, pp. 1650-1656Blair, D.F., How bacteria sense and swim (1999) Annu. Rev. Microbiol, 49, pp. 489-522Rao, C.V., Glekas, G.D., Ordal, G.W., The three adaptation systems of bacillus subtilis chemotaxis (2008) Trends Microbiol, 16, pp. 480-487Barros, V.C., Oliveira, J.S., Melo, M.N., Gontijo, N.F., Leishmania amazonensis: Chemotaxic and osmotaxic responses in promastigotes and their probable role in development in the phlebotomine gut (2006) Exp. Parasitol., 112, pp. 152-157Pfeffer, W., (1888) Unters. Botan. Inst., 2, pp. 582-661. , TubingenAdler, J., A method for measuring chemotaxis and use of the method to determine optimum conditions for chemotaxis by escherichia coli (1973) J. Gen. Microbiol., 74, pp. 77-91Alves, C.R., Albuquerque-Cunha, J.M., Mello, C.B., Nogueira, E.S.G.D.N.F., Bourguingnon, S.C., Souza, W.D., Azambuja, P., Gonzalez, M.S., Trypanosoma cruzi: Attachment to perimicrovillar membrane glycoproteins of rhodnius prolixus (2007) Experimental Parasitology, 116, pp. 44-52Fontes, A., Giorgio, S., De Castro Jr., A.B., Neto, V.M., De Pozzo, L.Y., Marques, G.P., Barbosa, L.C., Cesar, C.L., Determination of Femto Newton forces and fluid viscosity using optical tweezers - Application to Leishmania amazonensis (2005) Progress in Biomedical Optics and Imaging - Proceedings of SPIE, 5699, pp. 419-425. , DOI 10.1117/12.586427, 59, Imaging, Manipulation, and Analysis of Biomolecules and Cells: Fundamentals and Applications II

Multiwavelength studies of MHD waves in the solar chromosphere: An overview of recent results

The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly investigate the role waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.Comment: 48 pages, 25 figures, accepted into Space Science Review

Vascular Flora Of The Legado Das Águas, Reserva Votorantim, Municipalities Of Tapiraí, Miracatú And Juquiá, São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We present a list of vascular plants found in Legado das Águas, Reserva Votorantim, a private reserve having an area of approximately 35,000 ha that spans the municipalities of Tapiraí, Miracatú, and Juquiá, in the state of São Paulo, Brazil. The reserve is part of a complex of state-protected areas including Alto Ribeira Touristic State Park, Intervales State Park, Carlos Botelho State Park, Jurupará State Park, and Serra do Mar State Park. Together, these form an important and large area of continuous and well-preserved forest. Our study, which involved two main floristic surveys in March/April 2013 and April 2014, recorded 768 species, representing 131 families and 432 genera. The majority of species were angiosperms (619) representing 106 families and 370 genera. There were also two species of gymnosperms belonging to two genera in separate families; 147 species of ferns and lycophytes belonging to 23 families and 60 genera. In demonstrating the presence of almost 800 species of plants, of which 16 are threatened, our study highlights the importance of floristic surveys and the critical role of private protected areas in managing and preserving native flora. © 2016 Check List and Authors.1262011/22923-8, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2015/9444-4, FAPESP, Fundação de Amparo à Pesquisa do Estado de São PauloFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, \nobreak{$6\times 10^{19}$eV}. The anisotropy was measured by the fraction of arrival directions that are less than $3.1^\circ$ from the position of an active galactic nucleus within 75 Mpc (using the V\'eron-Cetty and V\'eron $12^{\rm th}$ catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is $(38^{+7}_{-6})$, compared with $21$ expected for isotropic cosmic rays. This is down from the early estimate of $(69^{+11}_{-13})$. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.Comment: Accepted for publication in Astroparticle Physics on 31 August 201