Structural And Morphological Investigation Of Magnetic Nanoparticles Based On Iron Oxides For Biomedical Applications

The present work reports the synthesis, characterization and properties of magnetic iron oxide nanoparticles for biomedical applications, correlating the nanoscale tunabilities in terms of size, structure, and magnetism. Magnetic nanoparticles in different conditions were prepared through thermal decomposition of Fe(acac)3 in the presence of 1,2 hexadecanodiol (reducing agent) and oleic acid and oleylamine (ligands) in a hot organic solvent. The 2,3-dimercaptosuccinic acid (DMSA) was exchanged onto the nanocrystal surface making the particles stable in water. Nanoparticles were characterized by X-ray diffraction (XRD) measurements, small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Preliminary tests of incorporation of these nanoparticles in cells and their magnetic resonance image (MRI) were also carried out. The magnetization characterizations were made by isothermal magnetic measurements. © 2007 Elsevier B.V. All rights reserved.284489494Bulte, J.W., Kraitchman, D.L., (2004) Curr. Pharm. Biotechnol., 5, p. 567Delikatny, E.J., Poptani, H., (2005) Radiol. Clin. North Am., 43, p. 205Lanza, G.M., Winter, P.M., Caruthers, S.D., Morawski, A.M., Schmieder, A.H., Crowder, K.C., (2004) J. Nucl. Cardiol., 11, p. 733Vymazal, J., Bulte, J.W., Frank, J.A., Di Chiro, G., Brooks, R.A., (1993) J. Magn. Reson. Imaging, 3, p. 637Hogemann, D.J.L., Weissleder, R., Basilion, J.P., (2000) Bioconjug. Chem., 11, p. 941Roullin, V.G., Deverre, J.R., Lemarie, L., Hindré, F., Julienne, M.C.V., Vienet, R., Benoit, J.P., (2002) Eur. J. Pharm. Biopharm., 53, p. 293Shinkai, M., Yanase, M., Suzuki, M., Honda, H., Wakabayashi, T., Yoshida, J., Kobayashi, T., (1999) J. Magn.Magn. Mater., 194, p. 44Mornet, S., Vasseur, S., Grasset, F., Duguet, E., (2004) J. Mater. Chem., 14, p. 2161Murray, C.B., Kagan, C.R., Bawendi, M.G., (2000) Annu. Rev. Mater. Sci., 30, p. 545Wang, X., Zhuang, J., Peng, Q., Li, Y.D., (2005) Nature, 437, p. 121Hyeon, T., (2003) Chem. Commun., 3, p. 927Brust, M., Kiely, C.J., (2002) Colloids Surf., 202, p. 175Park, J., Kang, E., Son, S.U., Park, H.M., Lee, M.K., Kim, J., Kim, K.W., Hyeon, T., (2005) Adv. Mater., 17, p. 429Jun, Y.W., Huh, Y.M., Choi, J.S., Lee, J.H., Song, H.T., Kim, S., Yoon, S., Cheon, J., (2005) J. Am. Chem. Soc., 127, p. 5732Gupta, A.K., Gupta, M., (2005) Biomaterials, 26, p. 3995Song, H.T., Choi, J.S., Huh, Y.M., Kim, S., Jun, Y.W., Suh, J.S., Cheon, J., (2005) J. Am. Chem. Soc., 127, p. 9992Arbab, A.S., Bashaw, L.A., Miller, B.R., Jordan, E.K., Bulte, J.W.M., Frank, J.A., (2003) Transplantation, 76, p. 1123Sun, S., Zeng, H., (2002) J. Am. Chem. Soc., 124, p. 8204Sun, S., Zeng, H., Robinson, D.B., Raoux, S., Rice, P.M., Wang, S.X., Li, G., (2004) J. Am. Chem. Soc., 126, p. 273Kellermann, G., Vicentin, F., Tamura, E., Rocha, M., Tolentino, H., Barbosa, A., Craievich, A., Torriani, I., (1997) J. Appl. Cryst., 30, p. 880Svergun, D.I., (1992) J. Appl. Cryst., 25, p. 495Metze, K., Andrade, L.A., (1991) Pathol. Res Pract., 187, p. 1031Alborghetti, M.R., Correa, M.E., Adam, R.L., Metze, K., Coracin, F.L., Souza, C.A., Cintra, M.L., (2005) J. Oral Pathol. Med., 34, p. 486Klug, H.P., Alexander, L.E., (1974) X-ray Diffraction Procedures for Polycrystalline and Amorphous Materials, p. 1. , John Wiley & Sons, New YorkFauconnier, N., Pons, J.N., Roger, J., Bee, A.J., (1997) J. Colloid Interface Sci., 194, p. 427Smith, D.R., Woolard, D., Luck, M.L., Laughlin, N.K., (2000) Toxicol. Appl. Pharm., 166, p. 23

Observaçoes sobre o parasitismo de Gallilichus hiregoudari D'souza & Jagannath (Acari: Syringobiidae) em Gallus gallus (L.) em infestações naturais

<abstract language="eng">The occurence of Gallilichus hiregoudari D'Souza e Jagannath in Gallus gallus (L.) is widespread in Brazil. All life stages of the mite can be found within the quills of primaries and secondaries of the flight feathers. Nymphal heteromorphism, imbalanced sex ratio toward females and thanatochresis are common features. Damage of the pulp caps and raquis are common pathological findings

TRMT5 Mutations Cause a Defect in Post-transcriptional Modification of Mitochondrial tRNA Associated with Multiple Respiratory-Chain Deficiencies

Contains fulltext : 154074.pdf (Publisher’s version ) (Open Access)Deficiencies in respiratory-chain complexes lead to a variety of clinical phenotypes resulting from inadequate energy production by the mitochondrial oxidative phosphorylation system. Defective expression of mtDNA-encoded genes, caused by mutations in either the mitochondrial or nuclear genome, represents a rapidly growing group of human disorders. By whole-exome sequencing, we identified two unrelated individuals carrying compound heterozygous variants in TRMT5 (tRNA methyltransferase 5). TRMT5 encodes a mitochondrial protein with strong homology to members of the class I-like methyltransferase superfamily. Both affected individuals presented with lactic acidosis and evidence of multiple mitochondrial respiratory-chain-complex deficiencies in skeletal muscle, although the clinical presentation of the two affected subjects was remarkably different; one presented in childhood with failure to thrive and hypertrophic cardiomyopathy, and the other was an adult with a life-long history of exercise intolerance. Mutations in TRMT5 were associated with the hypomodification of a guanosine residue at position 37 (G37) of mitochondrial tRNA; this hypomodification was particularly prominent in skeletal muscle. Deficiency of the G37 modification was also detected in human cells subjected to TRMT5 RNAi. The pathogenicity of the detected variants was further confirmed in a heterologous yeast model and by the rescue of the molecular phenotype after re-expression of wild-type TRMT5 cDNA in cells derived from the affected individuals. Our study highlights the importance of post-transcriptional modification of mitochondrial tRNAs for faithful mitochondrial function