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Cavicchioli M.,Sao Paulo State University | Massabni A.C.,Sao Paulo State University | Heinrich T.A.,University of Sao Paulo | Costa-Neto C.M.,University of Sao Paulo | And 6 more authors.
Journal of Inorganic Biochemistry | Year: 2010

Two new complexes of platinum(II) and silver(I) with acesulfame were synthesized. Acesulfame is in the anionic form acesulfamate (ace). The structures of both complexes were determined by X-ray crystallography. For K2[PtCl2(ace)2] the platinum atom is coordinated to two Cl- and two N-acesulfamate atoms forming a trans-square planar geometry. Each K+ ion interacts with two oxygen atoms of the S(O)2 group of each acesulfamate. For the polymeric complex [Ag(ace)]n the water molecule bridges between two crystallographic equivalent Ag1 atoms which are related each other by a twofold symmetry axis. Two Ag1 atoms, related to each other by a symmetry centre, make bond contact with two equivalent oxygen atoms. These bonds give rise to infinite chains along the unit cell diagonal in the ac plane. The in vitro cytotoxic analyses for the platinum complex using HeLa (human cervix cancer) cells show its low activity when compared to the vehicle-treated cells. The Ag(I) complex submitted to in vitro antimycobacterial tests, using the Microplate Alamar Blue (MABA) method, showed a good activity against Mycobacterium tuberculosis, responsible for tuberculosis, with a minimal inhibitory concentration (MIC) value of 11.6μM. The Ag(I) complex also presented a promising activity against Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis) microorganisms. The complex K2[PtCl2(ace)2] was also evaluated for antiviral properties against dengue virus type 2 (New Guinea C strain) in Vero cells and showed a good inhibition of dengue virus type 2 (New Guinea C strain) replication at 200μM, when compared to vehicle-treated cells. © 2010 Elsevier Inc. Source

De Araujo Junior A.M.,Sao Paulo State University | Braido G.,Sao Paulo State University | Saska S.,Sao Paulo State University | Barud H.S.,Sao Paulo State University | And 7 more authors.
Carbohydrate Polymers | Year: 2016

Regenerated cellulose scaffolds (RCS) may be used as alloplastic materials for tissue repair. In this work, the RCS were obtained by viscose process and characterized by scanning electron microscopy (SEM), wide angle X-ray diffraction (WAXD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry analysis (TG). In vitro enzymatic degradation assay and toxicological assays were also evaluated. The physicochemical characterizations revealed the formation of a porous material with distinct thermal profile and crystallinity compared to pristine cellulose pulp. Enzymatic degradation assay revealed that lysozyme showed a mildest catalytic action when compared to cellulase, Tricoderma reesei (Tr). Nevertheless, both enzymes were efficient for degrading the RCS. RCS did not show cytotoxicity, mutagenic or genotoxic effects. The systematically characterization of this work suggests that RCS presented distinct features that make it a viable material for future studies related to the development of scaffolds for biological applications. © 2015 Elsevier Ltd. All rights reserved. Source

Figueiredo R.V.,University of Sao Paulo | Amaral A.C.,Centro Universitario Of Araraquara Uniara | Shimano A.C.,University of Sao Paulo
Brazilian Journal of Physical Therapy | Year: 2012

Objective: To identify whether flight training activities cause postural changes in cadets and pilots of the Brazilian Air Force Academy (AFA). Methods: Eighty subjects were assessed through photographic images in anterior and right side views. Four groups of cadets (n=20 per group) divided according to the year since enlistment and a fifth group of fifteen pilots from the Air Demonstration Squadron (ADS) were included. Pictures were analyzed using the Postural Analysis Program (SAPO) and angles related to head vertical alignment (HVA), head horizontal alignment (HHA), acromion horizontal alignment (AHA) and anterior-superior iliac spine horizontal alignment (HAS) were plotted. Results: We did not find statistical significant differences in the angles: HVA, HHA and AHA. However, a significant difference was found for the HAS angle with pilots having lower values than cadets, suggesting greater postural stability for this variable in pilots. Conclusion: The horizontal alignment of the anterior-superior iliac spine was the only measure that showed significant difference in the comparison between pilots and cadets. The remaining alignments were not different, possibility because of the strict criteria used for admission of cadets at the AFA and the efficiency of the physical training that is performed periodically. © Revista Brasileira de Fisioterapia. Source

Lustosa G.M.M.M.,Sao Paulo State University | da Costa J.P.C.,Centro Universitario Of Araraquara Uniara | Perazolli L.A.,Sao Paulo State University | Stojanovic B.D.,University of Belgrade | Zaghete M.A.,Sao Paulo State University
Journal of the European Ceramic Society | Year: 2015

Recently, there has been an important rise in the research and development aimed to improve the properties of SnO2-based varistors. Meanwhile, due to fact that ZnO-based varistors possess better electrical properties compared to SnO2-based varistors, it is shown that it is needful to add additives to improve their properties. In our study, the SnO2-powder was prepared by the chemical route (Pechini method) with addition of ZnO (1mol%) and Nb2O5 (0.05mol%). Films were obtained by the electrophoretic deposition of SnO2-based powder, following by microwave oven sintering. Cr3+ was deposited by EPD on the films surface and thermal treatment was carried out in a microwave oven. After electrical characterization the films showed nonlinear coefficient over 10, breakdown voltage around 60V, low leakage current (Ω10-6A) and resistance over 200kΩcm. This indicates the efficiency of the used techniques to prepare varistor films with improved electrical properties after Cr3+ diffusion. © 2015 Elsevier Ltd. Source

Abbehausen C.,University of Campinas | Heinrich T.A.,University of Sao Paulo | Abrao E.P.,University of Sao Paulo | Costa-Neto C.M.,University of Sao Paulo | And 3 more authors.
Polyhedron | Year: 2011

A new silver(I) complex with N-acetyl-l-cysteine (NAC) of composition AgC5H8NO3S·H2O was synthesized and characterized by a set of chemical and spectroscopic measurements. Solid-state 13C nuclear magnetic resonance (SSNMR) and infrared (IR) analyses indicate the coordination of the ligand to Ag(I) through the sulfur atom. The Ag-NAC complex is slightly soluble in dimethyl sulfoxide. It is insoluble in water, methanol, ethanol, acetone and hexane. Antibacterial activity of the silver complex with N-acetyl-l-cysteine (Ag-NAC) was evaluated by antibiogram assays using the disc diffusion method. The compound showed an effective antibacterial activity against Staphylococcus aureus (Gram-positive), Escherichia coli and Pseudomonas aeruginosa (Gram-negative) bacterial cells. Biological analysis for evaluation of a potential cytotoxic effect of Ag-NAC was performed using HeLa cells derived from human cervical adenocarcinoma. The complex presented a significant cytotoxic activity, inducing 80% of cell death at a concentration of 200 μmol L-1. © 2010 Elsevier Ltd. All rights reserved. Source

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