In this study, we report a rapid sonochemical synthesis of monodisperse nonaggregated Fe(3)O(4)@SiO(2) magnetic nanoparticles (NPs). We found that coprecipitation of Fe(II) and Fe(III) in aqueous solutions under the effect of power ultrasound yields smaller Fe(3)O(4) NPs with a narrow size distribution (4-8 nm) compared to the silent reaction. Moreover, the coating of Fe(3)O(4) NPs with silica using an alkaline hydrolysis of tetraethyl orthosilicate in ethanol-water mixture is accelerated many-fold in the presence of a 20 kHz ultrasonic field. The thickness of the silica shell can be easily controlled in the range of several nanometers during sonication. Mossbauer spectra revealed that nonsuperparamagnetic behavior of obtained core-shell NPs is mostly related to the dipole-dipole interactions of magnetic cores and not to the particle size effect. Core-shell Fe(3)O(4)@SiO(2) NPs prepared with sonochemistry exhibit a higher magnetization value than that for NPs obtained under silent conditions owing to better control of the deposited silica quantities as well as to the high speed of sonochemical coating, which prevents the magnetite from oxidizing.

Blocking angiogenesis is an attractive strategy to inhibit tumor growth, invasion, and metastasis. We describe here the structure and the biological action of a new cyclic peptide derived from vascular endothelial growth factor (VEGF). This 17-amino acid molecule designated cyclopeptidic vascular endothelial growth inhibitor (cyclo-VEGI, CBO-P11) encompasses residues 79 -93 of VEGF which are involved in the interaction with VEGF receptor-2. In aqueous solution, cyclo-VEGI presents a propensity to adopt a helix conformation that was largely unexpected because only ␤-sheet structures or random coil conformations have been observed for macrocyclic peptides. Cyclo-VEGI inhibits binding of iodinated VEGF 165 to endothelial cells, endothelial cells proliferation, migration, and signaling induced by VEGF 165 . This peptide also exhibits anti-angiogenic activity in vivo on the differentiated chicken chorioallantoic membrane. Furthermore, cyclo-VEGI significantly blocks the growth of established intracranial glioma in nude and syngeneic mice and improves survival without side effects. Taken together, these results suggest that cyclo-VEGI is an attractive candidate for the development of novel angiogenesis inhibitor molecules useful for the treatment of cancer and other angiogenesis-related diseases.Angiogenesis takes place during embryonic development and in the adult during wound healing and the female ovulatory cycle. In pathological states, angiogenesis is observed during solid tumor growth and metastasis, diabetic retinopathy, and chronic inflammatory disorders. A number of angiogenic regulators such as vascular endothelial growth factors (VEGFs),

FT-IR spectrometry has proved to be a useful tool for determining a series of plasma molecular concentrations. Dedicated experiments were first performed to test the analytical performance that could be obtained by FT-IR spectrometry using a synthesized N3-peptide exhibiting a -N3 absorption centered at 2110 cm(-1), a spectral region where no organic material of biological samples absorbs. Further, we investigated whether this technology was able to allow quantification of metabolic parameters (glucose and lactic acid) within plasma, cells, and tissues as an alternative method to the "classical" biochemical approaches, which require sophisticated biological material treatment and expensive reagents. For this purpose we used a series of plasma samples to determine glucose and lactic acid concentrations, which are common markers of cancer growth. We compared the results of the main spectral data treatments commonly achieved for FT-IR data analysis, such as univariate (Beer-Lambert) or multivariate (PLS) calibrations, as well as the deconvolution of the spectral interval of interest (1200-900 cm(-1)). No significant differences were found regarding the analytical performances of these methods. Spectral deconvolution was finally undertaken on cultured and on xenografted cells (U87 glial cells implied in human gliomas) to determine glucose and lactic acid concentrations. In this case, qualification was allowed by FT-IR imaging on the cellular models since biochemical approaches are not efficient to reach metabolic concentrations at the cellular level while keeping tissue organization.

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